ECRIS2010 - List of Keywords (ion)

Paper	Title	Other Keywords	Page
MOCOAK01	SECRAL Status and First Beam Test at 24GHz	ECR, heavy-ion, ion-source, plasma	1
	H.W. Zhao, Y. Cao, Y.C. Feng, X.H. Guo, J.Y. Li, W. Lu, L.T. Sun, D. Xie, X.Z. Zhang, H. Zhao IMP, Lanzhou, People's Republic of China
	SECRAL has been in routine operation at 18GHz for HIRFL (Heavy Ion Research Facility in Lanzhou) accelerator complex since May 2007. It has delivered many highly charged heavy ion beams for the HIRFL accelerator and the total beam time so far has exceeded 3000 hours. To further enhance the SECRAL performance, a 24GHz/7kW gyrotron microwave amplifier has been installed and tested. Very exciting results were produced with quite a few new record highly-charged ion beam intensities. Bremstrahlung measurements at 24GHz have shown that X-ray is much stronger at higher RF frequency, higher RF power and higher minimum B field. Beam emittance study has been conducted in order to improve the beam brightness. An additional cryostat with five GM cryocoolers was installed atop the SECRAL to liquefy the boil-off helium gas to minimize the liquid helium consumption. The latest results and reliable long-term operation for the accelerator have once again demonstrated that SECRAL is one of the best performance ECR ion source for the production of highly-charged heavy ion beams. Detailed and future developments of SECRAL will be presented.
	Slides MOCOAK01 [4.739 MB]

MOCOAK02	Intense Beam Production with SuSI	ECR, ion-source, ECRIS, plasma	4
	L.T. Sun, J. Brandon, D.G. Cole, M. Doleans, G. Machicoane, D. Morris, T. Ropponen, L. Tobos NSCL, East Lansing, Michigan, USA E. Pozdeyev FRIB, East Lansing, Michigan, USA
	SuSI ion source, a 3rd generation fully superconducting ECR ion source is now used for injection into the Coupled Cyclotron Facility since September 2009. Initial performances during the commissioning of SuSI were mainly limited by the microwave power available from a single 18 GHz microwave amplifier, especially for the production of heavier ion beams. The Injection of SuSI was modified to add a second 18 GHz amplifier, to reach a maximum of 3.0 kW of RF power inside the plasma chamber. Production of heavy ion beams, such as Kr¹⁴⁺, Bi³⁰⁺ and U³³⁺ is reported, to demonstrate the performance of SuSI. Additional studies were made with various ion source parameters to optimize the beam intensity within a normalized emittance of 0.9pi.mm.mrad as needed for the FRIB project and will be reported in this paper.
	Slides MOCOAK02 [1.672 MB]

MOCOAK03	Status of RIKEN SC-ECRIS	ECR, ion-source, ECRIS, heavy-ion	8
	T. Nakagawa, Y. Higurashi, J. Ohnishi RIKEN Nishina Center, Wako, Japan T. Aihara, M. Tamura SHI Accelerator Service Ltd., Tokyo, Japan
	To increase the beam intensity of highly charged heavy ions for RIKEN RIBF project, we constructed and tested RIKEN new SC-ECRIS. After obtaining the first beam in the spring of 2009, we tried to optimize the ion source condition for maximizing the beam intensity with 18GHz microwave. In this experiment, we intensively studied the effect of the magnetic field gradient and ECR zone size on the beam intensity. In this experiment, it was clearly seen that the gentler field gradient and lager ECR zone size give higher beam intensity. Based on these studies, we produced 550μA of Ar¹¹⁺ and 350μA of Ar¹²⁺ at the RF power of 1.8kW. In this summer, we will try use the 28GHz microwaves to increase the beam intensity. In this contribution, we present the structure of the SC-ECRIS and the results of test experiments with 18 GHz microwave in detail. We also present the future plan to increase the beam intensity.
	Slides MOCOAK03 [2.366 MB]

MOCOAK04	Status of the VENUS ECR Ion Source	ion-source, ECR, plasma, cyclotron	11
	D. Leitner, P. Ferracin, A. Hodgkinson, M. Leitner, T.J. Loew, C.M. Lyneis, G.L. Sabbi LBNL, Berkeley, California, USA G. Machicoane, E. Pozdeyev NSCL, East Lansing, Michigan, USA
	The fully superconducting 28-GHz VENUS ECR ion source serves as prototype injector for the Facility for Rare Isotope Beams (FRIB) project at Michigan State University (MSU) as well as injector ion source for the 88-Inch Cyclotron at Lawrence Berkeley National Laboratory (LBNL). As such the source has produced many record beams of high charge state as well as high-intensity, medium charge state ions. As the FRIB project has now entered the preliminary design phase, Lawrence Berkeley National Laboratory is involved in the design of two new VENUS-like ECR injector ion sources for the FRIB facility. This paper will review the requirements for the FRIB injector, and present VENUS cryostat design changes which will allow installation on a 100 kV platform. In addition, a possible future upgrade path for the FRIB injector using an advanced Nb3Sn magnet structure is described. In 2008, at LBNL the VENUS ECR ion source experienced a major setback when one of the sextupole leads evaporated during a quench caused by a low liquid helium level in the cryostat. The repair process and the long reconstruction effort as well as the status of the reinstallation will be described.
	Slides MOCOAK04 [4.180 MB]

MOCOBK01	ECR Ion Sources for the Facility for Rare Isotope Beams (FRIB) Project at Michigan State University	ion-source, ECR, linac, emittance	14
	G. Machicoane, M. Doleans, O.K. Kester, T. Ropponen, L.T. Sun, X. Wu NSCL, East Lansing, Michigan, USA D. Leitner LBNL, Berkeley, California, USA E. Pozdeyev, E. Tanke FRIB, East Lansing, Michigan, USA
	Funding: Work supported by US DOE Cooperative Agreement DE-SC0000661 Once operational, the Facility for Rare Isotope Beams (FRIB) will open the possibility to gain key understanding in nuclear science and in particular regarding the properties of nuclei far from the valley of stability or the nuclear processes in the universe. In addition it will also allow experimenters to test fundamental symmetries. The production of rare isotopes with FRIB will be achieved, using a heavy ion driver linac that will accelerate a stable isotope beam to 200 MeV/u and deliver it on a fragmentation target. FRIB aims to reach a primary beam power of 400 kW for light to heavy elements up to Uranium. To meet the intensity requirement two high performance ECR ion sources operating at 28 GHz will be used to produce high intensity of medium to high charge state ion beams. Plans regarding initial beam production with the ECR ion sources and beam transport through the front end will be discussed.
	Slides MOCOBK01 [3.259 MB]

MOCOBK02	Present Status of FLNR (JINR) ECR Ion Sources	ion-source, cyclotron, ECR, injection	17
	S.L. Bogomolov, V.B. Bekhterev, V.M. Drobin, A. Efremov, B. Gikal, G.G. Gulbekyan, Yu.K. Kostyukhov, N. Lebedev, V.N. Loginov, V.V. Seleznev, Yu. Yazvitsky JINR, Dubna, Moscow Region, Russia
	Six ECR ion sources have been operated in the Flerov Laboratory of Nuclear Reactions (JINR). Two 14 GHz ECR ion sources (ECR4M and DECRIS-2) supply various ion species for the U400 and U400M cyclotrons correspondingly for experiments on the synthesis of heavy and exotic nuclei using ion beams of stable and radioactive isotopes. The 18 GHz DECRIS-SC ion source with superconducting magnet system produce ions from Ar up to W for solid state physics experiments and polymer membrane fabrication at the CI-100 cyclotron. The third 14 GHz ion source DECRIS-4 with “flat” minimum of the axial magnetic field is used as a stand alone machine for test experiments and also for experiments on ion modification of materials. The other two compact ECR ion sources with all permanent magnet configuration have been developed for the production of single charged ions and are used at the DRIBs installation and at the MASHA mass-spectrometer. In this paper, present status of the ion sources, recent developments and plans for modernization are reported. Also the results of the preliminary test of the DECRIS-SC2 ECR source will be presented.
	Slides MOCOBK02 [11.671 MB]

MOCOBK03	Status of Ion Sources at HIMAC	ion-source, ECR, plasma, radiation	20
	A. Kitagawa, M. Muramatsu, Y. Sakamoto NIRS, Chiba-shi, Japan S. Biri ATOMKI, Debrecen, Hungary A.G. Drentje KVI, Groningen, The Netherlands T.F. Fujita National Institute of Radiological Sciences, Chiba, Japan T. Sakuma, N. Sasaki, T. Sasano, W. Takasugi AEC, Chiba, Japan
	Since 1994, heavy-ion radiotherapy using carbon ions is successfully carried out with the Heavy Ion Medical Accelerator in Chiba (HIMAC) at the National Institute of Radiological Sciences (NIRS). Over 5000 cancer patients have already been treated with 140-400 MeV/u carbon beams. These clinical results have clearly verified the advantages of carbon ion. The ion source needs to realize a stable beam with the same conditions for daily operation. Maintenance is restricted to once per year. However, the deposition of carbon on the wall of the plasma chamber is normally unavoidable. This causes an ‘anti-wall-coating effect’, i.e. a decreasing of the beam (typically 50 % after a few months of operation), especially for the higher charge-state ions due to the surface material of the wall. The ion source has - even in this bad condition – still to produce a sufficiently intense and stable beam. We summarize our experience during 16 years of operation and show the scope for further developments. HIMAC is dedicated to radiotherapy, but it has as a second essential task to operate as a facility for physicist users. In that scope it accelerates many ion species for basic experiments. In order to serve all HIMAC users at best, the extension of the range of ion species is an important subject in ion source development. For example, in order to increase the ECRIS-beam intensity for heavier ions, microwave is applied at different frequencies by a traveling wave tube amplifier and….?
	Slides MOCOBK03 [2.780 MB]

MOCOBK04	Recent Activities at the ORNL Multicharged Ion Research Facility (MIRF)	ECR, plasma, electron, permanent-magnet	23
	F.W. Meyer, M.E. Bannister, S. Deng, I.N. Draganić, J.W. Hale, P.R. Harris, C.C. Havener, H.F. Krause, C.R. Vane ORNL, Oak Ridge, Tennessee, USA
	Funding: Sponsored by the Office of Fusion Energy Sciences and the Office of Basic Energy Sciences of the U.S. DOE under contract No. DE-AC05-00OR22725 with UT_Battelle. We report on recent upgrades of the ORNL Multicharged Ion Research Facility, and our activities in the area of ECR ion source diagnostic measurements. The upgrades include installation of a new all permanent magnet ECR ion source [1] on a high voltage platform that increases our high energy beam production capability to 250keV/q, and installation of a floating beamline fed by a 10 GHz CAPRICE ECR ion source for producing decelerated ion beams to energies as low as a few eV/q range. The primary application of all the produced ion beams is to study fundamental collisional interactions [2] of multicharged ions with electrons, atoms, and surfaces. We also summarize recent diagnostic measurements of the ECR plasma potential and other plasma parameters using an in-situ Langmuir probe installed in the ECR edge plasma and complementary measurements [3] using an external beam deceleration method. [1] D. Hitz et al. , “An All-Permanent Magnet ECR Ion Source for the ORNL MIRF Upgrade Project,” AIP Conference Proceedings 749, 123 (2005), Woodbury, NY. [2] F.W. Meyer, “ECR-Based Atomic Collision Physics Research at ORNL MIRF,” in Trapping Highly Charged Ions: Fundamentals and Applications, J. Gillaspy, ed., Nova Science Pub., New York, 2000, pp. 117-164. [3] P.R. Harris and F.W. Meyer, Rev. Sci. Inst. 81, 02A310 (2010).
	Slides MOCOBK04 [2.645 MB]

MOCOCK01	PK-ISIS: a New Superconducting ECR Ion Source at Pantechnik	permanent-magnet, extraction, ECR, ion-source	26
	A.C.C. Villari, C. Bieth, W. Bougy, B.N. Brionne, X. Donzel, G. Gaubert, R. Leroy, A. Sineau, O. Tasset, C. Vallerand PANTECHNIK, BAYEUX, France T. Thuillier LPSC, Grenoble, France
	The new ECR ion source PK-ISIS was recently commissioned at Pantechnik. Three superconducting coils generate the axial magnetic field configuration while the radial magnetic field is done with multi-layer permanent magnets. Special care was devoted in the design of the hexapolar structure, allowing a maximum magnetic field of 1.32 T at the wall of the 82 mm diameter plasma chamber. The three superconducting coils using Low Temperature Superconducting wires are cooled by a single double stage cryo-cooler (4.2 K). Cryogen-free technology is used, providing reliability, easy maintenance at low cost. The maximum installed RF power (18.0 GHz) is of 2 kW. Metallic beams can be produced with an oven (Tmax = 1400 °C) installed with an angle of 5° with respect to the source axis or a sputtering system, mounted in the axis of the source. The beam extraction system is constituted of three electrodes in accel-decel configuration. Description of the source and results of the magnetic measurements will be given. Performances of the source in terms of beam intensities and charge states distribution will be presented.
	Slides MOCOCK01 [3.226 MB]

MOCOCK02	3D Simulation Studies and Optimization of Magnetic Holes of HTS-ECRIS for Improving the Extraction Efficiency and Intensities of Highly Charged Ions	plasma, ECR, extraction, ion-source	27
	G. Rodrigues, R.N. Dutt, D. Kanjilal, P.S. Lakshmy, Y. Mathur, U.K. Rao, A. Roy IUAC, New Delhi, India R. Baskaran IGCAR, Channai, India
	3D simulation studies using RADIA code have been performed to optimise the magnetic holes in high temperature superconducting electron cyclotron resonance (HTS-ECRIS) ion source for improving the extraction efficiency and intensities of highly charged ions. The magnetic field improvements using simple techniques like optimisation of iron regions is found to be economical. The extraction efficiency can be increased three-fold in the case of a hexapole magnet depending on the level of the uniformity of the fields in the high and low regions. This technique further minimises localized heating of the plasma chamber walls which can improve the vacuum conditions in an ECR ion source. For superconducting sources where the x-ray heat load poses severe problems during operation, such a reduction of heating load is of great significance. The typical triangular pattern of the plasma impact observed on the plasma electrode of HTS ECRIS at various tuning conditions are reproduced by the simulations. Details of the simulations and experimental results will be presented.
	Slides MOCOCK02 [2.925 MB]

MOCOCK03	Design Study of a Higher Magnetic Field SC ECRIS at IMP	ECRIS, plasma, solenoid, sextupole	30
	D. Xie, W. Lu, X.Z. Zhang, H.W. Zhao IMP, Lanzhou, People's Republic of China
	Development of ECR ion source has demonstrated that, as the empirical scaling laws summarized, higher magnetic field with higher operation frequencies will greatly improve the source performance. Based on the great success of SECRAL, a higher magnetic field SC ECRIS is planned to meet the new accelerator demands at IMP. However, there are many practical issues in the design and construction of a higher field SC ECRIS that need to be addressed. In this paper we will present and discuss the design features of the higher field SC ECR with a maximum axial field of 7.0 T and a radial field of 3.5 T at the plasma chamber inner surface, and operating frequency up to 50 GHz.
	Slides MOCOCK03 [1.825 MB]

MOCOCK05	Multigan®: a New Multicharged Ion Source Based on Axisymetric Magnetic Structure	ECRIS, plasma, electron, extraction	37
	L. Maunoury, P. Delahaye, M. Dubois, P. Jardin, P. Lehérissier, M. Michel, J.Y. Pacquet GANIL, Caen, France S. Biri ATOMKI, Debrecen, Hungary X. Donzel, G. Gaubert, R. Leroy, A.C.C. Villari PANTECHNIK, BAYEUX, France C. Pierret CIMAP, Caen, France
	Standard ECR ion sources have radial magnetic field created by a multi-pole, e.g. hexapole or higher order, which fills all space in the center of the source structure. Based on the Monogan® ECRIS [1] concept, a new multicharged ECR ions source has been designed with a large opening space in the center of the source structure. This particular design allows, in a first approach, direct radial contact with the ECR plasma, allowing positioning of probes and targets for radioactive beam production very close to the plasma region. Secondly, the absence of a multi-pole allows considering extremely high magnetic fields with significantly smaller structural constraints. This source is combining the advantages of the axisymetric magnetic feature of Monogan® with higher frequencies. This paper will describe the magnetic structure calculation as well as the mechanical design and stresses of a full permanent magnet ion source using this concept. This source will be the first prototype of such an ECR ion source. Finally, using TrapCad code [2], an estimation of the electronic energy distribution has been calculated and thus, the performance of the source has been deduced. The beam formation and extraction were also roughly calculated taking into account magnetic and electric fields. [1] P. Jardin et al., Review of Scientific Instruments, 73, 789 (2002). [2] L. Maunoury et al., Plasma Sources Science and Technology , 18, 015019 (2009).
	Slides MOCOCK05 [5.532 MB]

MOPOT001	Operation of KeiGM for the Carbon Ion Therapy Facility at Gunma University	extraction, heavy-ion, ion-source, vacuum	40
	M. Muramatsu, S. Hojo, A. Kitagawa NIRS, Chiba-shi, Japan Y. Kijima Mitsubishi Electric Corp., Energy & Public Infrastructure Systems Center, Kobe, Japan H. Miyazaki, K. Sawada, T. Ueno SHI, Ehime, Japan K. Torikai, S. Yamada Gunma University, Heavy-Ion Medical Research Center, Maebashi-Gunma, Japan M. Tsuchiyama, S. Ueda Mitsubishi Electric Corp., Energy Systems Centre, Kobe, Japan
	Carbon-ion radiotherapy has been carried out at Gunma University Heavy Ion Medical Centre (GHMC) since March 2010. A compact ECR ion source for GHMC, so-called KeiGM, supplies C⁴⁺ ions for treatment. A microwave source with the traveling-wave-tube was adopted for KeiGM, with a frequency range and maximum power of 9.75 - 10.25 GHz and 750 W, respectively. KeiGM was operated from March to May 2010 for the clinical trial without any trouble and maintenance. KeiGM supplied the carbon ions from 7:30 in the morning to 0:00 midnight on weekdays. Sometimes it was operated for the beam tuning of accelerator on Saturday and Sunday too. The operation time of KeiGM for two months was about 780 hours. Although the beam intensity decreased by 20% at first, it has been constant for the last two months. The beam intensity of C⁴⁺ was 200 euA at 30 kV extraction in May 2010. The fluctuation of beam intensity was less than 10%. The operation parameters were as follows; the microwave frequency and power were 10.042 GHz and 300 W, respectively. CH4 gas was fed, and the gas flowrate was 0.054 cc/min. The extraction voltage was 30 kV. The repetition frequency and pulse width were 0.36 Hz and 50 msec, respectively. Gunma University has successfully treated the first 12 patients for the clinical trial, thus the Japanese Ministry of Health and Labor Welfare approved GHMC as “advanced medicine”. We will report the operation of KeiGM and the status of their daily treatment.
	Poster MOPOT001 [2.685 MB]

MOPOT002	Two-Chamber Configuration of the Bio-Nano ECRIS	plasma, ECRIS, extraction, resonance	43
	T. Uchida, H. Minezaki, Y. Yoshida Toyo University, Kawagoe-shi, Saitama, Japan T. Asaji, K. Tanaka Tateyama Machine Co. Ltd., Toyama-shi, Japan S. Biri, R. Rácz ATOMKI, Debrecen, Hungary Y. Kato Osaka University, Graduate School of Engineering, Osaka, Japan A. Kitagawa, M. Muramatsu NIRS, Chiba-shi, Japan
	The Bio-Nano ECRIS was designed for new materials production on nano-scale [1]. Our main target is the endohedral fullerene, which have potential in medical care, biotechnology and nanotechnology. In particular, iron-encapsulated fullerene can be applied as a contrast material for magnetic resonance imaging or microwave heat therapy. There are several promising approaches to produce the endohedral fullerenes using an ECRIS. One of them is the ion-ion collision reaction of fullerenes and aliens ions to be encapsulated in the mixture plasma of them. Another way is the shooting of ion beam into a pre-prepared fullerene layer. In this study, the new device configuration of the Bio-Nano ECRIS is reported which allows the application of both methods. The plasma chamber is divided into two chambers by installing mesh electrodes. In the gas injection-side 1st chamber at 2.45 GHz plasmas (N₂, Ar, He, Fe,) are produced on the usual way. These ions then are extracted to the 2nd chamber where an evaporation boat for fullerene is installed. The fullerene neutrals can be ionized (using 10 GHz in the 2nd chamber) and are deposited on a large plasma electrode where they are continuously irradiated by the ions from the 1st chamber. The ions produced either in the 1st or 2nd chamber can be in-situ extracted and analyzed. The basic concept and the preliminary results using Ar gas and N₂ gas plasmas will be presented. [1] T. Uchida et al., Proc. ECRIS08, Chicago, USA, pp. 27-31 (2008)
	Poster MOPOT002 [6.248 MB]

MOPOT003	Study of Potential Application of Compact ECRIS to Analytical System	ECR, ion-source, plasma, permanent-magnet	46
	M. Kidera RIKEN Nishina Center, Wako, Japan S. Enomoto Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan S. Kishi, Y. Seto National Research Institute of Police Science, Chiba, Japan T. Nagamatsu, T. Tanaka Tokyo University of Science, Faculty of Engineering Division I, Tokyo, Japan K. Takahashi RIKEN, Saitama, Japan
	A place of an activity of ECR ion sources is not only ion source on a heavy ion accelerator facility. A highly ionization efficiency, flexibility of ionized sample, low consumption rate in sample, and non-equilibrium ECR plasma, etc. that a ECR ion source have, may be needed in other fields at time. We have developed several kinds of small ECRISs that have customized for the analysis. The purposes of the analysis are, precise measurement of isotope ratio of a metal element, detection of chemical warfare agents, and detection of produced molecular (or fragment) ions by the ECR plasma. In this workshop, we will report the compact ECRISs by a permanent magnet type for the analytical system.
	Poster MOPOT003 [3.320 MB]

MOPOT004	Neutralisation of Accelerated Ions and Detection of Resulting Neutrals	ion-source, ECR, simulation, acceleration	49
	T. Peleikis, L. Panitzsch, M. Stalder IEAP, Kiel, Germany
	At the University of Kiel, the Department of Experimental and Applied Physics is running an ECR ion source in order to, amongst others, calibrate space instruments designed to measure solar wind properties and suprathermal particles. The ion source is able to produce medium to highly charged ions which are then accelerated by an electrostatic field up to 400keV per charge. In order to extend the particle spectrum from ions to neutral atoms we are planning to install a device for the beam particle neutralisation. It will be used to calibrate instruments which measure neutral particles. This device will be located downstream from the sector magnet and the acceleration-stage. The sector magnet separates the ions by their m/q ratio. This way the type and the energy of the ions can be determined before the neutralisation. Neutralisation can be achieved either by passing the ions through a thin carbon foil (thickness ~88nm) or through a gastarget (thickness ~6mm, pressure ~0.1mbar) where charge-exchange occur. The remaining ions behind the neutraliser will be suppressed by an electrostatic separator. Both methods will alter the beam properties and lead to a divergence in energy and an angular spread of the beam. Simulations regarding these effects will be discussed. The overall progress on this project will be presented.
	Poster MOPOT004 [1.776 MB]

MOPOT005	High Current Production with 2.45 GHz ECR Ion Source	extraction, ECR, ion-source, plasma	50
	A. Coly, T. Lamy, T. Thuillier LPSC, Grenoble Cedex, France G. Gaubert, A.C.C. Villari PANTECHNIK, BAYEUX, France
	A new test bench has been installed at LPSC dedicated to 2.45 GHz ECR Ion Sources characterization. Several magnetic structures have been tested around the same plasma cavity. For example, a current density of 70 mA/cm² has been measured with the MONO1000 source lent by GANIL. An original ECRIS, named SPEED (for 'Source d'ions à aimants PErmanents et Extraction Dipôlaire'), presenting a dipolar magnetic field at the extraction will also be presented.
	Poster MOPOT005 [3.130 MB]

MOPOT006	Ionization Efficiency of a COMIC Ion Source Equipped With a Quartz Plasma Chamber	plasma, ion-source, target, injection	51
	P. Suominen, T. Stora CERN, Geneva, Switzerland J. Médard, P. Sortais LPSC, Grenoble, France
	The ISOLDE facility at CERN produces a wide range of radioactive ion beams due to a long history on target and ion source development. Because the radioactive isotope production is very limited, the most important ion source parameters are high ionization efficiency, selectivity and reliable operation under intense radiation. Currently used ion sources (mainly laser (RILIS [1]) and arc discharge -type ion sources (VADIS [2]) do not efficiently ionize light noble gases, such as helium, and molecules, such as CO, N₂ and NO. These beams were previously planned to be produced with 1+ ECR ion sources operating at 2.45 GHz (for example MINIMONO [3]) but due to new and more efficient RF coupling of COMIC-type ion sources [4], we expect to advance in 2.45 GHz ECRIS utilization for radioactive beam production. The new COMIC source designed by LPSC, Grenoble incorporates special features such as a plasma chamber fully made of quartz (Q-COMIC). This should provide chemically good conditions for molecular ion beam production, especially for carbon. This paper presents the first ionization efficiency measurements of the Q-COMIC. [1] V.N. Fedosseev, et al, Nucl. Instrum. Methods Phys. Res. B 266/19-20 (2008) 4378. [2] PhD thesis, univ. polyt. Bucarest, L. Penescu (2009). [3] F. Wenander, W. Farabolini, G. Gaubert, P. Jardin, J. Lettry, Nucl. Phys. A, 746 (2004) 659. [4] P. Sortais, T. Lamy, J. Médard, J. Angot, L. Latrasse, and T. Thuillier, Rev. Sci. Instrum. 81 (2010) 02B314.
	Poster MOPOT006 [0.697 MB]

MOPOT008	He²⁺ Source Based on Penning Discharge with Additional 75 GHz ECR Heating	plasma, ECR, radiation	54
	A. Vodopyanov, S. Golubev, I. Izotov, A. Mansfeld IAP/RAS, Nizhny Novgorod, Russia G. Yushkov Institute of High Current Electronics, Tomsk, Russia
	It is well known that one can reach high average charge of ions in the ECR plasma by increasing plasma density and decreasing neutral gas pressure. ECR discharge could be realized at very low gas pressure, but discharge startup takes longer time when gas pressure is low. So, it is impossible to realize ECR discharge with limited microwave heating pulse duration at gas pressure lower certain threshold value. This problem could be solved with help of trigger plasma, which should be ignited at low gas pressure in the trap with high magnetic field. This fore plasma could help to decrease ECR plasma startup time significantly and make it possible to realize ECR plasma at very low pressure in pulse operation regime. We suggest penning type discharge as a trigger discharge for fast startup of pulsed ECR plasma. Penning type discharge glows at as low pressure as needed. Discharge was realized in the simple mirror magnetic trap at pressure about 10^-5 mbar. Helium was used as an operating gas. Significant plasma density (about 10¹¹ cm^-3) was obtained at the moment just before microwave heating pulse started. Gyrotron radiation with frequency of 75 GHz, microwave power up to 200 kW and pulse duration up to 1 ms, was used for plasma heating. In the present work the fully striped helium ions were demonstrated, average charge of ions in the plasma was equal 2. Temporal evolution of charge state distribution was investigated. Charge state distribution over helium pressure was also studied.
	Poster MOPOT008 [0.535 MB]

MOPOT010	The Light Ion Guide CB-ECRIS Project at the Texas A&M University Cyclotron Institute	ECRIS, cyclotron, light-ion, plasma	55
	G. Tabacaru Texas A&M University, Cyclotron Institute, College Station, USA J. Ärje JYFL, Jyväskylä, Finland D.P. May Texas A&M University Cyclotron Institute, College Station, Texas, USA
	Texas A&M is currently configuring a scheme for the production of radioactive-ion beams that incorporates a light-ion guide (LIG) coupled with an ECRIS constructed for charge-boosting (CB-ECRIS). This scheme is part of an upgrade to the Cyclotron Institute and is intended to produce radioactive beams suitable for injection into the K500 superconducting cyclotron. The principle of operation is the following: a primary beam from the K150 cyclotron interacts with a production target placed in the gas cell. A continuous flow of helium gas maintains a constant pressure of 500 mbar maximum in the cell. Recoils are thermalized in the helium buffer gas and ejected from the cell within the gas flow through a small exit hole. The positively charged recoil ions (1+) are guided into a 2.5 m long, rf-only hexapole and will be transported in this manner on-axis into the CB-ECRIS. The CB-ECRIS operates at 14.5 GHz and has been specially constructed by Scientific Solutions of San Diego, California for charge-boosting. An overview of the entire project will be presented with details on different construction phases. Specific measurements and results will be presented as well as future development plans.
	Poster MOPOT010 [12.413 MB]

MOPOT013	MONOBOB II : Latest Results of Monocharged Ion Source for SPIRAL2 Project	target, ECRIS, plasma, vacuum	64
	M. Dubois, O. Bajeat, C. Barue, C. Canet, M. Dupuis, J.L. Flambard, R. Frigot, P. Jardin, C. Leboucher, N. Lecesne, P. Lecomte, P. Lehérissier, F. Lemagnen, L. Maunoury, O. Osmond, J.Y. Pacquet, A. Pichard GANIL, Caen, France
	MONOBOB II is an electron cyclotron resonance ion source (ECRIS) based on a cylindrical symmetry magnetic structure [1]. It has been designed for the SPIRAL2 project in order to ionize radioactive gases coming from the production targets of the Target Ion Source System (TISS). The goal is to build a long-lived ECRIS with the aim of running three months in the hostile environment of the production target while keeping high ionization efficiencies. The Target Ion Source System has been tested using noble gases (He, Ne, Ar, Kr and Xe), with and without target in order to observe the behavior of the source coupled to the target. Currently, the target is made of ~1000 carbon slices, having the same geometry as the final UCx target. So far, its temperature has been limited to 1500°C. Ionization efficiencies and response times of the TISS have been measured versus gases and target temperature [2]. Results should lead to determine the maximum radioactive ion production which can be reasonably expected with the final TISS. The status of this development will be presented.
	Poster MOPOT013 [0.858 MB]

MOPOT014	The Design of 28 GHz ECR Ion Source for the Compact Linear Accelerator in Korea	ECRIS, ion-source, extraction, ECR	67
	M. Won, B.S. Lee Korea Basic Science Institute, Busan, Republic of Korea
	The construction of a compact linear accelerator is in progress by Korea Basic Science Institute. The main capability of this facility is the production of multiply ionized metal clusters and the generation more intense beams of highly charged ions for material, medical and nuclear physical research. To produce the intense beam of highly charged ions, we will construct an Electron Cyclotron Resonance Ion Source (ECRIS) using 28 GHz microwaves. For this ECRIS, The design of a superconducting magnet, microwave inlet, beam extraction and plasma chamber was completed. Also we are constructing a superconducing magnet system. In this presentation, we will report the current status of development of our 28 GHz ECRIS.
	Poster MOPOT014 [3.823 MB]

MOPOT015	The Design Study of Superconducting Magnet System for an Advanced ECR Ion Source	superconducting-magnet, ECRIS, ion-source, ECR	68
	B.S. Lee, M. Won Korea Basic Science Institute, Busan, Republic of Korea
	Funding: This work was supported by KBSI grant (D30300) to M.S.Won The Korea Basic Science Institute is developing a superconducting magnet system for 28 GHz Electron Cyclotron Resonance Ion Souce (ECRIS). We are invetigating in order to realize compact size, economic operation and generation of high current beam. Although companies and researchers have valuable experience, skill and ability in designing of superconducting magnet for ECRIS, they did not exactly proposed a excellent superconducting magnet system for ECRIS because many superconducting magnets were not required. Of course they do if we requried many magnets for the various appliation of ECRIS. In this presentation, we have filed reports of former reseacher and we have discussed the realization of ECRIS over 35 GHz.
	Poster MOPOT015 [7.135 MB]

MOPOT016	A Low Power Survey of Radial-Offset Axial Sputtering and High Intensity Uranium Production from Axial Sputtering in SuSI	target, plasma, injection, survey	69
	D.G. Cole, G. Machicoane, T. Ropponen, L.T. Sun, L. Tobos NSCL, East Lansing, Michigan, USA
	Prototype sputtering hardware has been tested in the SuSI ion source and early uranium ion production is discussed. Also, results of a low power survey of axial sputtering, to test sputtering efficiency at incremental radial offsets from on axis position, is reported.
	Poster MOPOT016 [2.672 MB]

MOPOT017	Tests of a New Axial Sputtering Technique in an ECRIS	plasma, ECRIS, ECR, injection	72
	R.H. Scott, R.C. Pardo, R.C. Vondrasek ANL, Argonne, USA
	Funding: This work is supported by the U.S. Department of Energy, Office of Nuclear Physics, under contract No. DE-AC02-06CH11357. Axial and radial sputtering techniques have been used over the years to create beams from an ECRIS at multiple accelerator facilities. Operational experience has shown greater beam production when using the radial sputtering method versus axial sputtering. At Argonne National Laboratory, previous work with radial sputtering has demonstrated that the position of the sputter sample relative to the plasma chamber wall influences sample drain current, beam production and charge state distribution. The possibility of the chamber wall acting as a ground plane which influences the sputtering of material has been considered, and an attempt has been made to mimic this possible ground plane effect with a coaxial sample introduced from the injection end. Results of these tests will be shown as well as comparisons of outputs using the two methods.
	Poster MOPOT017 [1.506 MB]

TUCOAK01	First A/Q=3 Beams of Phoenix V2 on the Heavy Ions Low Energy Beam Transport Line of SPIRAL2	ion-source, ECRIS, dipole, heavy-ion	75
	C. Peaucelle IN2P3 IPNL, Villeurbanne, France J. Angot, P. Grandemange, T. Lamy, T. Thuillier LPSC, Grenoble Cedex, France J.-L. Biarrotte IPN, Orsay, France D. Uriot CEA/DSM/IRFU, France
	The heavy ions low energy beam transport line (LEBT) of Spiral2 built at LPSC Grenoble is fully operational since the beginning of 2010. This LEBT has been calculated and designed to hold permanently 15 mA of multicharged ions extracted from the source at 60 kV. PHOENIX V2 ECRIS is presently installed on the LEBT and first tests started few months ago: A reliable beam of 1 mAe of O⁶⁺ beam at 45 kV has already been obtained for a long period with a very good transmission, and good reproducibility. Tests continue with an optimization of Ar¹²⁺ beam performance. The promising results of these first runs, particularly emittance measurements, profiles and optimization of charge optics will be presented along. The ECRIS Phoenix V2 and different equipments installed on this line (vacuum system, optic elements, diagnostics) will be described. The future program and planned improvements on the LEBT will be also discussed in this paper.
	Slides TUCOAK01 [2.402 MB]

TUCOAK02	Trace Space Reconstruction From Pepperpot Data	emittance, simulation, beam-transport, ECRIS	78
	H.R. Kremers, J.P.M. Beijers, S. Brandenburg, V. Mironov, J. Mulder, S. Saminathan KVI, Groningen, The Netherlands
	We use a pepperpot emittance meter to determine the full transverse trace-space distribution of low-energy ion beams. One of the problems encountered with our emittance meter is that the correlation between the measured ion images and the holes in the pepperplate is somewhat ambiguous caused by the convoluted character of the trace-space distribution. In this paper we describe a method to solve this problem and illustrate it with measurements of the 4d transverse trace-space distribution behind the analyzing magnet of a 21 keV He¹⁺ beam extracted from the KVI-AECR ion source. From these measurements together with ion-transport simulations we conclude that second-order aberrations in the analyzing magnet cause a significant increase in the effective beam emittance.
	Slides TUCOAK02 [3.474 MB]

TUCOAK03	Plasma-to-Target WARP Simulations of Uranium Beams Extracted from VENUS Compared to Emittance Measurements and Beam Images	simulation, extraction, ion-source, emittance	81
	D. Winklehner, J.Y. Benitez, D. Leitner, M.M. Strohmeier, D.S. Todd LBNL, Berkeley, California, USA D.P. Grote LLNL, Livermore, California, USA
	The superconducting ECR ion source VENUS was built as injector for the 88-Inch Cyclotron at Lawrence Berkeley National Laboratory (LBNL) and as prototype injector for the Facility for Rare Isotope Beams (FRIB) in Michigan. This work presents the latest results of an ongoing effort to simulate both, the extraction from ECR ion sources, and the Low Energy Beam Transport (LEBT). Its aim is to help understand the influence of parameters like initial ion distributions at the extraction aperture, ion temperatures and beam neutralization on the quality of the beam and to provide a design-tool for increasing the efficiency of the extraction- and transport-system. The initial conditions (i.e. spatial- and velocity-distribution of the ions prior to extraction from the ion source) are obtained semi-empirically by tracking the ions of different species from sputter marks on the biased disk on the far end of the source to the extraction region by following the magnetic field lines and scaling the Larmor radii of the ions appropriately. Extraction from the plasma and consequently the source is then simulated with the versatile WARP simulation code. The same code is also used for the actual simulation of ion transport through the beam line. Simulations of multi-species Uranium beams with different drain currents, initial ion temperatures and levels of neutralization in the beam line are compared to each other and to emittance measurements and beam profiles of VENUS beams.
	Slides TUCOAK03 [2.382 MB]

TUCOAK04	Production of Highly Charged U Ion Beam from RIKEN SC-ECRIS	emittance, ECRIS, extraction, target	84
	Y. Higurashi, M. Fujimaki, A. Goto, H. Haba, E. Ikezawa, O. Kamigaito, M. Kase, M. Komiyama, T. Nakagawa, J. Ohnishi, Y. Watanabe RIKEN Nishina Center, Wako, Japan T. Aihara, M. Tamura, A. Uchiyama SHI Accelerator Service Ltd., Tokyo, Japan
	In 2008, we successfully produced 345 MeV/u U beam (~0.4 pnA on target) for RIKEN RIBF project. However, to meet the requirement of the RIBF (primary beam intensity of 1pμA on target), we still need to increase the beam intensity. To increase the beam intensity of U ion, we started to make a test experiments for production of U ion beam from the new SC-ECRIS. In this experiment, we produced 2~1.5 pμA of medium charge state U ion (ex., 55 eμA of U³¹⁺, 57 eμA of U²⁷⁺) at the RF power of 1.2 kW with sputtering method. For testing the effect of the ionized gas on the U ion beam, we chose Ar, Ar + O₂ and O₂ gas for producing U ion beam. In this experiment, we observed that the beam intensity of lower charge state of U ion beam (<33+) was increased and the emittance of the U ion beam was decreased from ~0.1 π.mm mrad (1rms) to 0.05 π.mm mrad with adding Ar gas to O₂ gas. Using this method, we supplied U³⁵⁺ beam for ~1 month without break for the RIBF experiment. In this contribution, we present the experimental results for production of U ion beam from SC-ECRIS in detail and future plan to increase the U ion beam intensity.
	Slides TUCOAK04 [1.709 MB]

TUCOBK01	Preglow Phenomenon Origins and its Scaling for Ecris	plasma, radiation, electron, ECR	87
	I. Izotov, V. Sidorov, V. Skalyga, V. Zorin IAP/RAS, Nizhny Novgorod, Russia
	Preglow effect investigation is one of topical directions of ECR ion sources development at present. Preglow is of interest for efficient short-pulsed multi-charged ion source creation. Particularly, such source of intense beams of short-living radioactive isotopes multi-charged ions is one of key elements in “Beta-Beam” European project [1]. Use of Preglow-generating regime of an ECRIS operation is a promising way of pulsed high-intense multi-charged ion beams production with much shorter edges in comparison with usual operation regime. The first theoretical investigations of Preglow phenomenon were performed in references [2,3]. Present work describes modified model of ECR discharge development in a magnetic trap of the ECRIS as a continuation of [2,3]. Numerical simulations made with the updated model allow authors to propose more physical and intuitive explanation of Preglow phenomenon origins. Obtained dependences of Preglow characteristics on experimental conditions offer a scaling for a wide range of ECRISes. [1] (ONLINE) http://beta-beam.web.cern.ch/beta-beam/task/diverse/mandate.htm [2] T. Thuillier et al, Rev. of Sci. Instrum., 79, 02A314, 2008. [3] I. Izotov et al, IEEE Trans. Plasma Sci. 36, 1494, 2008.
	Slides TUCOBK01 [0.928 MB]

TUCOBK02	“Preglow” Investigation in ECR Discharge at 37 GHz, 100 kW	plasma, ECR, ion-source, radiation	90
	V. Skalyga, I. Izotov, S. Razin, V. Sidorov, V. Zorin IAP/RAS, Nizhny Novgorod, Russia T. Lamy, T. Thuillier LPSC, Grenoble, France
	Multicharged ion beams generation in "Preglow" regime is now considered as the main way of short pulsed ion source creation for “Beta Beam” project. The "Preglow" effect has been investigated at a several laboratories (LPSC, JYFL, IAP RAS). The effect was discovered at LPSC on PHOENIX ion source using 18 GHz radiation for plasma heating. Investigations at 14 GHz frequency were made at JYFL. Theoretical analysis demonstrated the advantage of MW frequency increase. Theoretical calculations predict possibility of "Preglow" peaks generation with duration about tens microseconds and rather high average ion charge. At present time at LPSC a joint construction of a new generation ECR ion source with 60 GHz gyrotron plasma heating is running. As a continuation of previous research at 14, 18 and 28 GHz at present work results of experimental and theoretical "Preglow" effect investigations at SMIS 37 setup with 37,5 GHz MW plasma heating are reported. Received data are important as fundamental result in physics of ECRISs and at the same time it is the next step on the way of 60 GHz SEISM facility creation. “Preglow” effect was observed and investigated in experiments with ECR discharge stimulated with gyrotron radiation @ 37.5 GHz, 100 kW. Received dependencies of the “Preglow” parameters are in good correspondence with results of numerical simulations. It was shown in experiments that generation of “Preglow” peak with duration about 30 μs is possible.
	Slides TUCOBK02 [2.338 MB]

TUCOBK03	Time Evolution of Plasma Potential in Pulsed Operation of ECRIS	plasma, electron, ion-source, ECRIS	93
	O.A. Tarvainen, H. A. Koivisto, T. Ropponen, V.A. Toivanen JYFL, Jyväskylä, Finland Y. Higurashi, T. Nakagawa RIKEN Nishina Center, Wako, Japan
	The time evolution of plasma potential has been measured in pulsed operation mode with electron cyclotron resonance ion sources at JYFL and RIKEN. Three different ion sources with microwave frequencies ranging from 6.4 to 18 GHz were employed for the experiments. The plasma potential during the preglow and afterglow transients was compared with steady state conditions. The plasma potential was observed to increase 25-75 % during the preglow and 10-30 % during the afterglow. We describe the experimental procedure and present the results of the study in detail.
	Slides TUCOBK03 [0.973 MB]

TUCOBK04	Micropulses Generation in ECR Breakdown Stimulated by Gyrotron Radiation at 37.5 GHz	plasma, ECR, electron, ion-source	96
	V. Skalyga, S. Golubev, I. Izotov, S. Razin, V. Sidorov, A. Vodopyanov, V. Zorin IAP/RAS, Nizhny Novgorod, Russia
	Present work is devoted to experimental and theoretical investigation of possibility of short pulsed (< 100 μs) multicharged ion beams creation. The possibility of quasi-stationary generation of short pulsed beams under conditions of quasi-gasdynamic plasma confinement was shown in recent experiments. Later another way of such beams creation based on “Preglow” effect was proposed. In present work it was demonstrated that in the case when duration of MW pulse is less then formation time of “Preglow” peak, realization of a regime when ion current is equal to zero during MW pulse and intense multicharged ions flux appears only when MW ends could be possible. Such pulses after the end of MW were called "micropulses". In present work generation of micropulses was observed in experiments with ECR discharge stimulated by gyrotron radiation @ 37,5GHz, 100 kW. In this case pulses with duration less than 30 μs. Probably the same effect was observed in GANIL where 14 GHz radiation was used and pulses with duration about 2 ms were registered. In present work it was shown that intensity of such micropulse could be higher than intensity of “Preglow” peak at the same conditions but with longer MW pulse. The generation of micropulses of nitrogen and argon multicharged ions with current of a few mA and length about 30 μs after MW pulse with duration of 30-100 μs was demonstrated. The low level of impurities, high current density and rather high average charge make possible to consider such micropulse regime as perspective way for creation of a short pulsed ion source.
	Slides TUCOBK04 [3.473 MB]

TUCOCK01	Beam, Multi-Beam and Broad Beam Production with COMIC Devices	plasma, cavity, extraction, high-voltage	99
	P. Sortais, J. Angot, T. Lamy, J. Médard LPSC, Grenoble Cedex, France C. Peaucelle IN2P3 IPNL, Villeurbanne, France
	The COMIC discharge cavity is a very versatile technology. We will present new results and devices that match new applications like: molecular beams, ultra compact beam line for detectors calibrations, quartz source for on-line application, high voltage platform source, sputtering /assistance broad beams and finally, a quite new use, high energy multi¬-beam production for surface material modifications. In more details, we will show that the tiny discharge of COMIC can mainly produce molecular ions (H³⁺). We will present the preliminary operation of the fully quartz ISOLDE COMIC version, in collaboration with IPN-Lyon, we will present a first approach for a slit extraction version of a three cavity device, and after discussing about various extraction systems on the multi discharge device (41 cavities) we will show the low energy broad beam (2 KV) and high energy multi-beams (10 beams up to 30 KV) productions. We will specially present the different extraction systems adapted to each application and the beams characteristics which are strongly dependent on the voltage distribution of an accel-accel two electrodes extraction system.
	Slides TUCOCK01 [4.960 MB]

TUCOCK02	Status of the High Current Permanent Magnet 2.45 GHz ECR Ion Source at Peking University	ion-source, plasma, ECR, extraction	102
	S.X. Peng, J.E. Chen, Z.Y. Guo, P.N. Lu, Y.R. Lu, H.T. Ren, Z.Z. Song, J.X. Yu, Z.X. Yuan, M. Zhang, J. Zhao PKU/IHIP, Beijing, People's Republic of China
	Several compact 2.45 GHz Electron Cyclotron Resonance Ion Sources (ECRIS) have been developed at Peking University for ion implantation[1], separated function Radio Frequency quadruple (SFRFQ)[2] and for the Peking University Neutron Imaging Facility (PKUNIFTY)[3]. Studies are focused on methods of magnetic field generation, magnetic fields configuration, microwave window design, microwave coupling, and structure selection of extraction electrodes. Up to now, our sources have produced 25 mA O+/ He⁺ ion, 10mA N+ ion, 100 mA H⁺ and 83 mA D⁺ ions, respectively. Details will be reported in the paper. [1] Z. Song, D. Jiang, and J. Yu, Rev. Sci. Instr., 67,1003(1996). [2] S. X. Peng, M. Zhang, Z. Z. Song, R. Xu, J. Zhao, Z. X. Yuan, J. X. Yu, J. Chen, Z. Y. Guo, Rev. Sci. Instr., 2008, 79: 02B706. [3] M. Zhang, S. X. Peng, H. T. Ren, Z. Z. Song, Z. X. Yuan, Q. F. Zhou, P. N. Lu, R. Xu, J. Zhao, J. X. Yu, J. E. Chen, Z. Y. Guo, and Y. R. Lu, Rev. Sci. Instr. 2010, 81:02B715.
	Slides TUCOCK02 [3.144 MB]

TUCOCK03	Development of 14.5 GHz Electron Cyclotron Resonance Ion Source at KAERI	ECR, plasma, ion-source, extraction	105
	B.H. Oh, D.S. Chang, C.K. Hwang, S.R. In, S.H. Jeong, J.T. Jin, K.W. Lee, C.S. Seo KAERI, Daejon, Republic of Korea
	A 14 GHz ECRIS has been designed and fabricated in KAERI (Korea Atomic Energy Research Institute) to produce multi-charged ion beam (especially for C⁶⁺ ion beam) for medical applications. The magnet system has solenoid coils made with copper conductor and a hexapole made with permanent magnet. The solenoid coils are composed of two axial coils to make mirror fields in both sides of the chamber and one trim coil at the center to control the layer of the resonance region. The hexapole is made with 24-sector NdFeB permanent magnet. Radial field higher than 1.2 T at the chamber wall position has been measured, and axial field higher than 1.7 T at the entrance center of RF power and 1.1 T at the exit center of ion beam have been measured. A welded tube with aluminum and stainless steel is used for a ECR plasma chamber to improve the production of secondary electron. Cooling channel is made on the wall of the Al tube. A 2 kW Krystron is used as a microwave energy source. A DC break made with PEEK(Polyether Ether Ketone) for high voltage insulation and field shielding, and a RF window made with ceramic for vacuum insulation are inserted in the RF circuit. A movable beam extractor with 8 mm aperture covers different species and different charge numbers of the beam. Experimental results on ECR plasma and initial beam extraction with KAERI ECR ion source will be discussed.
	Slides TUCOCK03 [2.342 MB]

TUCOCK04	Mass Spectrometry with an ECR Ion Source	ion-source, background, ECR, controls	109
	M.A.C. Hotchkis, D. Button ANSTO, Menai, Australia
	Several groups [1-3] have demonstrated the usefulness of ECR ion sources in forms of mass spectrometry, for the detection of rare long-lived radioisotopes, trace elements and stable isotope ratios. Mass spectrometry imposes strict constraints on the ion source. First, the ion source must be free of backgrounds at the same m/q ratio as isotope of interest. Backgrounds take several forms, including beams generated from residual gas or other materials in the source, either of the element of interest, or other elements which cause isobaric or other m/q ambiguities. Second, the ion source must exhibit a minimum ‘memory’ effect from sample to sample. We are interested in isotopic ratios of carbon, nitrogen and oxygen. These elements are ubiquitous in vacuum systems and so this work has its own particular challenges, especially in relation to the design and operational characteristics of the ion source. Initial work has revealed retention effects which reduce the sample clear out rates, and cause persistent backgrounds [4]. We will present results of our most recent efforts to control these problems. [1] P. Collon et al., Nucl. Instrum. Methods B 2004; 223/224: 428. [2] M. Kidera et al., Eur. J. Mass Spectrom. 2007; 13: 239. [3] M. Hotchkis et al., Rapid Comm. Mass Spec. 2008; 22: 1408-1414. [4] D. Button and M.A.C. Hotchkis, Proc. 18th ECRIS Workshop, Sept 15-18, 2008, Chicago, USA, http://www. JACoW.org/.
	Slides TUCOCK04 [3.849 MB]

TUPOT001	Plans for Laser Ablation of Actinides into an ECRIS for Accelerator Mass Spectroscopy	laser, ECR, ion-source, ECRIS	110
	R.C. Pardo, F.G. Kondev, S.A. Kondrashev, C. Nair, T. Palchan, E. Rehm, R.H. Scott, R.C. Vondrasek ANL, Argonne, USA P. Collon University of Notre Dame, Notre Dame, USA G. Imel ISU, Pocatello, Idaho, USA C. McGrath, G. Palmotti, M. Salvatores, G. Youinou Idaho National Laboratory, Idaho, USA M. Paul The Hebrew University of Jerusalem, The Racah Institute of Physics, Jerusalem, Israel
	Funding: This work is supported by the U.S. Department of Energy, Office of Nuclear Physics, under contract No. DE-AC02-06CH11357. A project using accelerator mass spectrometry (AMS) at the ATLAS facility to measure neutron capture rates on a wide range of actinides in a reactor environment is underway. This project will require the measurement of many samples with high precision and accuracy. The AMS technique at ATLAS is based on production of highly-charged positive ions in an ECRIS followed by linear acceleration. We have chosen to use laser ablation as the best means of feeding the actinide material into the ion source because we believe this technique will have more efficiency and lower chamber contamination thus reducing ‘cross talk’ between samples. In addition a multi-sample holder/changer is part of the project to allow quick change between multiple samples. The status of the project, design, and goals for initial off-line ablation tests will be discussed as well as the overall project schedule.
	Poster TUPOT001 [0.152 MB]

TUPOT002	Enhancement of ECR Performances by Means of Carbon Nanotubes Based Electron Guns	electron, plasma, gun, ECR	114
	F. Odorici, M. Cuffiani, L. Malferrari, R. Rizzoli, G.P. Veronese INFN-Bologna, Bologna, Italy G. Castro, L. Celona, G. Ciavola, N. Gambino, S. Gammino, D. Mascali, R. Miracoli, F.P. Romano INFN/LNS, Catania, Italy T. Serafino Università di Messina, Messina, Italy
	One of the main goals of the scientific community which deals with ECR Ion Sources is the optimization of the Eelectron Energy Distribution Function (EEDF) inside the plasma. The EEDF consists of three different populations (cold, warm and hot electrons): the cold and the warm populations are responsible of the stabilization and of the efficient ionization of the plasma respectively. The presence of the hot population is doubly detrimental: in high frequency sources they lead to the heating of LHe in the superconducting coils’ cryostat and are also useless for the generation of high intensity ion beams, because of their small cross section. Therefore the injection of additional electrons inside the plasma may increase the density of cold and warm electrons, enabling at the same time to reduce the number of the high energy ones. The CANTES experiment tested the use of carbon nanotubes (CNTs) to emit electrons in presence of strong applied electric fields, in order to provide additional electrons to the plasma core. This technique was used with the Caesar ECR ion source, at INFN-LNS, demonstrating that the total extracted ion current is increased and that a relevant reduction of the number of “high energy” electrons (above 100 keV) can be obtained. This last result is even more important, because CNTs may be an effective and reliable tool to permit the operation of ECRIS at large power and high frequencies without any detrimental effect on the source stability and reliability coming from hot electrons. Details of the construction of CNTs based electron gun and their behaviour in plasma environments are presented. Preliminary results in terms of performances of the Caesar ECR ion source and possible future applications will be also discussed.
	Poster TUPOT002 [1.914 MB]

TUPOT003	A New BETSI Test Bench at CEA/Saclay	permanent-magnet, plasma, diagnostics, solenoid	117
	S. Nyckees, Y. Gauthier, C.M. Mateo CEA/IRFU, Gif-sur-Yvette, France G. Adroit, O. Delferrière, R.D. Duperrier, R. Gobin, F. Harrault, O. Napoly, B. Pottin, Y. Sauce, F. Senée, O. Tuske, T.V. Vacher CEA/DSM/IRFU, France
	By the 90s, CEA has undertaken to develop the production of high intensity light ion beams from plasma generated by electron cyclotron resonance (ECR). Important results were obtained with the SILHI source in pulsed or continuous mode. Presently, CEA/Saclay is now involved in the construction of different injectors dedicated to large infrastructures like IFMIF or Spiral 2. Other installations are also interested by high intensity ion sources like ESS or FAIR. To improve and test new sources, a new test bench named BETSI (Banc d'Etudes et de Tests des Sources d'Ions) is now operating for several months. Low energy beam line diagnostics consist of a Faraday cup, cameras and a species analyzer. The SILHI emittance scanner can also be installed on the beam line. On this test bench, different permanent magnet source configurations are tested. In order to modify plasma chamber size and shape, a new ECR source design is developed. An experimental study of the plasma visible light emitted through electrodes was implemented on BETSI using a monochromator. Extracted beam intensity of a permanent magnet source is compared to plasma light emission. Results obtained with monochromator will be compared with SOLMAXP code in order to explore radio frequency wave and plasma interaction.
	Poster TUPOT003 [4.044 MB]

TUPOT004	Microgan ECR Ion Source in a Van de Graaff Accelerator Terminal	ion-source, controls, high-voltage, ECR	120
	G. Gaubert, C. Bieth, W. Bougy, B.N. Brionne, X. Donzel, A. Sineau, O. Tasset, C. Vallerand, A.C.C. Villari PANTECHNIK, BAYEUX, France C. Chavez-de-Jesus, T. Gamboni, W. Geerts, G. Giorginis, R. Jaime Tornin, G. Lövestam, W. Mondelaers JRC/IRMM, Geel, Belgium
	The Van de Graaff accelerator at IRMM works since many years providing proton, deuteron and helium beams for nuclear data measurements. The original ion source was of RF type with quartz bottle. This kind of source, as well known, needs regular maintenance for which the accelerator tank must be completely opened. The heavy usage at high currents of the IRMM accelerator necessitated an opening about once every month. Recently, the full permanent magnet Microgan ECR ion source from PANTECHNIK was installed into a new terminal platform together with a solid state amplifier of 50W, a dedicated dosing system for 4 gases (with respective gas bottles H2, D2, He and Ar), and a set of dedicated power supplies and electronic devices for the remote tuning of the source. The new system shows a very stable behavior of the produced beam allowing running the Van de Graff without maintenance for several months. This contribution will describe the full installed system in details (working at high pressure in the terminal, spark effects and optic of the extraction).
	Poster TUPOT004 [1.715 MB]

TUPOT005	An ECR Table Plasma Generator	plasma, ECR, ECRIS, vacuum	124
	R. Rácz, S. Biri ATOMKI, Debrecen, Hungary J. Pálinkás DU, Debrecen, Hungary
	A simple ECR plasma device was built in our lab using the “spare parts” of the ATOMKI ECR ion source. We call it “ECR table plasma generator”. It consists of a relatively big plasma chamber (ID=10 cm, L=40 cm) in a thin NdFeB hexapole magnet with independent vacuum and gas dosing systems. For microwave coupling two low power TWTAs can be applied individually or simultaneously, operating in the 6-18 GHz range. There is no axial magnetic field and there is no extraction. The intended fields of usage of the plasma generator are: A simple, cheap and safe educational working place for students. To prepare, to test or to simulate measurements with electrostatic movable Langmuir probes. The exchange time of the (damaged) probes is very short. To prepare, to test or to simulate plasma diagnostic measurements in the visible light and X-ray ranges using cameras and spectrometers. To cover and/or to modify solid surfaces with plasma particles, including fullerenes. In the paper the technical details of the plasma generator and some preliminary plasma photo results are shown.
	Poster TUPOT005 [0.871 MB]

TUPOT006	Using Mass-Flow Controllers for Obtaining Extremely Stable ECR Ion Source Beams	injection, ECR, controls, ion-source	127
	X. Donzel, W. Bougy, B.N. Brionne, G. Gaubert, A. Sineau, O. Tasset, C. Vallerand, A.C.C. Villari PANTECHNIK, BAYEUX, France R. Leroy GANIL, Caen, France
	Beam stability and reproducibility is of paramount importance in applications requiring precise control of implanted radiation dose, like in the case of Hadrontherapy. The beam intensity over several weeks or months should be kept constant. Moreover, the timing for changing the nature of the beam and, as a consequence, the tuning of the source should be minimized. Standard valves usually used in conjunction of ECR ion sources have the disadvantage of controlling the conductance, which can vary significantly with external conditions, like ambient temperature and inlet pressure of the gas. The use of flow controllers is the natural way for avoiding these external constraints. In this contribution we present the results obtained using a new model of Mass-flow controller in the source Supernanogan, for production of C⁴⁺ and H³⁺ beams. Extremely stable beams (± 2.5%) without retuning of the source over several weeks could be obtained. The reproducibility of the source tuning parameters could also be demonstrated.
	Poster TUPOT006 [4.386 MB]

TUPOT007	Preliminary Design of BLISI, an Off Resonance Microwave Proton Source	plasma, extraction, proton, resonance	130
	S. Djekic, I. Bustinduy, D. Cortazar, D. Fernandez-Cañoto, H. Hassanzadegan, J.L. Munoz, D. de Cos ESS Bilbao, Bilbao, Spain F.J. Bermejo Bilbao, Faculty of Science and Technology, Bilbao, Spain M.A. Carrera, J.H. Galipienzo AVS, Eibar, Gipuzkoa, Spain V. Etxebarria, J. Jugo, J. Portilla University of the Basque Country, Faculty of Science and Technology, Bilbao, Spain J. Feuchtwanger, I. Rueda ESS-Bilbao, Zamudio, Spain J. Lucas Elytt Energy, Madrid, Spain
	A new high current off resonance microwave H⁺ source is currently in the last stages of design at ESS-Bilbao, in collaboration with two external companies Elytt and AVS. The design is intended to be a high-stability, high-current ion source capable of delivering a 70 mA proton beam with a 70 keV energy at the end of the extraction. The plasma system designed by Elytt consists of a water-cooled plasma chamber that sits between two independently powered magnetic coils that generate the ECR magnetic field; in addition they can be moved independently to further shape the magnetic field in the chamber. A CPI 2.7 GHz klystron provides the microwave energy and a fully controlled microwave system to minimize reflected power and improve the source overall performance is also under construction. The extraction column designed by AVS will consist of a movable tetrode system designed for a maximum acceleration potential of 70 kV, the shape of the electrodes is at an earlier design stage at ESS-Bilbao. We will present the current layout of the source, simulations and schematics of the source.
	Poster TUPOT007 [3.954 MB]

TUPOT008	Performance of the LBNL AECR-U with a TWTA	plasma, resonance, coupling, ion-source	133
	J.Y. Benitez, D. Leitner, C.M. Lyneis LBNL, Berkeley, California, USA M.K. Covo LLNL, Livermore, California, USA
	The Advanced Electron Cyclotron Resonance - Upgrade ion source (AECR-U) at the Lawrence Berkeley National Laboratory has successfully utilized double frequency microwave heating (14.3 GHz and 10.4 GHz) for several years [1]. Recently a traveling wave tube amplifier (TWTA), providing frequencies in the range of 10.75GHz-12.75GHz, was added as a secondary heating frequency, replacing the previous 10.4 GHz Klystron. The TWTA opens the possibility to explore a wide range of secondary frequencies and a study has been conducted to understand and optimize its coupling into the AECR-U. In particular, the reflected power dependence on heating frequency has been mapped out with and without the presence of plasma. A comparison is made to determine how the presence of plasma, confinement fields, and other source parameters affect the reflected power and if and how the amount of reflected power can be correlated to the source ion beam performance. [1] Z. Q. Xie and C. M. Lyneis, Rev. Sci. Instrum. 66 (1995).
	Poster TUPOT008 [0.213 MB]

TUPOT009	Measurements of Bremsstrahlung Radiation and X-Ray Heat Load to Cryostat on SECRAL	radiation, electron, ECR, plasma	134
	H. Zhao, Y. Cao, X.X. Li, D. Xie, W.H. Zhang, X.Z. Zhang, H.W. Zhao, Y.H. Zhu IMP, Lanzhou, People's Republic of China W. Lu Graduate School of the Chinese Academy of Sciences, Beijing, People's Republic of China
	Measurement of Bremsstrahlung radiation from ECR plasma can yield certain information of the ECR heating process and a plausible estimate of the X-ray heat load to the cryostat of a superconducting ECR source which needs seriously addressed. With a newly-developed collimation system, which defines a narrower spatial range of the measurement and provides an effective shielding from the background, a systematic measurement of the Bremmstrahlung emitted axially from the SECRAL (Superconducting ECR Ion Source with Advanced design in Lanzhou) plasma were carried out recently. The spectral temperature Tspe, a relative index of mean energy of the plasma hot electrons, was derived through linear fitting of the spectra in semi-logarithm coordinates. This article will present and discuss the evolutions of the X-ray flux and the hot electron energy with various source parameters, such as heating frequency, RF power and magnetic field configuration. And possible solutions to reduce the X-ray heat load induced by Bremsstrahlung radiation are proposed and discussed.
	Poster TUPOT009 [1.581 MB]

TUPOT010	Effects of Microwave Frequency Fine Tuning on the Performance of JYFL 14 GHz ECRIS	plasma, ion-source, emittance, ECRIS	137
	V.A. Toivanen, V.P. Aho, J. Ärje, P. Jones, J.A. Kauppinen, H. A. Koivisto, P. Peura, O.A. Tarvainen JYFL, Jyväskylä, Finland L. Celona, G. Ciavola, S. Gammino INFN/LNS, Catania, Italy A. Galatà INFN/LNL, Legnaro (PD), Italy D. Mascali CSFNSM, Catania, Italy T. Ropponen NSCL, East Lansing, Michigan, USA
	Measurements have been carried out at Department of Physics, University of Jyväskylä (JYFL) to study the effects of microwave frequency fine tuning on the performance of JYFL 14 GHz electron cyclotron resonance ion source. The frequency was varied within an 85 MHz band around the normal operation frequency of 14.085 GHz. The radial bremsstrahlung emission was measured for plasma diagnostics purposes and mass separated ion beam currents extracted from the ion source were recorded at the same time. Also, beam quality studies were conducted by measuring the ion beam emittance and shape with and without enhanced space charge compensation. The obtained results are presented and possible origins of seen phenomena in measured quantities are discussed.
	Poster TUPOT010 [0.678 MB]

TUPOT012	Microwave Frequency Dependence of the Properties of the Ion Beam Extracted From a Caprice Type ECRIS	plasma, ECRIS, ECR, ion-source	143
	F. Maimone, R. Lang, J. Mäder, J. Roßbach, P. Spädtke, K. Tinschert GSI, Darmstadt, Germany L. Celona INFN/LNS, Catania, Italy F. Maimone DMFCI, Catania, Italy
	In order to improve the quality of ion beams extracted from ECR ion sources it is mandatory to better understand the relations between the plasma conditions and the beam properties. The present investigations concentrate on the analysis of different beam properties under the influence of various applications of frequency tuning and of multiple frequency heating. The microwave frequency feeding the plasma affects the electromagnetic field distribution and the dimension and position of the ECR surface inside the plasma chamber. This in turn has an influence on the generation of the extracted ion beam in terms of its intensity, of its shape and of its emittance. In order to analyze the corresponding effects measurements have been performed with the Caprice type ECRIS installed at the ECR Injector Setup (EIS) of GSI. The experimental setup uses a new arrangement of one or more microwave sweep generators which feed a Traveling Wave Tube amplifier covering a wide frequency range from 12.5 to 18 GHz. This arrangement provides a precise determination of the frequencies and of the reflection coefficient along with the beam properties. A sequence of viewing targets positioned inside the beam line monitors the beam shape.
	Poster TUPOT012 [1.245 MB]

TUPOT013	Influence of Initial Plasma Density and Mean Electron Energy on the Preglow Effect	plasma, simulation, electron, ECR	146
	I. Izotov, V. Sidorov, V. Skalyga, V. Zorin IAP/RAS, Nizhny Novgorod, Russia H. A. Koivisto, O.A. Tarvainen, V.A. Toivanen JYFL, Jyväskylä, Finland
	The investigation of the Preglow effect is driven with the aim of creating a short-pulsed multicharged ion source. Recent experimental investigations have revealed strong influence of seed electrons, i.e. initial plasma density, on the amplitude and duration of the Preglow peak [1]. Present work, consisting of experiments and simulations, is dedicated to further investigation of the Preglow dependence on initial plasma density and electrons energy. Experimental investigation was performed at University of Jyväskylä (JYFL) with the A-ECR type ECRIS operated with 14 GHz frequency. Helium was used for the study. An initial ionization degree of the gas was varied by changing the pulse duration and duty factor. Time-resolved ion currents of He⁺ and He²⁺ were recorded. Calculations were made by using 0-dimensional model described in references [2], [3] and based on the balance equations for the particles confined in the magnetic trap. Results of simulation are compared with experimental Preglow peaks and discussed. Good agreement between experimental data and simulation encourages us to conduct a further study, aimed at optimizing the Preglow by tuning source parameters and initial plasma conditions. [1] O. Tarvainen et al, Rev. Sci. Instrum., 81, 02A303, 2010. [2] T. Thuillier et al, Rev. Sci. Instrum., 79, 02A314, 2008. [3] I. Izotov et all. IEEE Trans. Plasma Sci. 36, 1494, 2008.
	Poster TUPOT013 [0.569 MB]

TUPOT014	Optimized Extraction Conditions From High Power ECRIS by Dedicated Dielectric Structures	plasma, extraction, electron, ECRIS	147
	L. Schächter, S. Dobrescu IFIN, Magurele- Bucuresti, Romania K.E. Stiebing IKF, Frankfurt-am-Main, Germany
	The MD-method of enhancing the ion output from ECR ion sources is well established and basically works via two mechanisms, the regenerative injection of cold electrons from an emissive dielectric layer on the plasma chamber walls and via the cutting of compensating wall currents, which results in an improved ion extraction from the plasma. As this extraction from the plasma becomes a more and more challenging issue for modern ECRIS installations with high microwave power input, a series of experiments was carried out at the 14 GHz ECRIS of the Institut für Kernphysik in Frankfurt/Main, Germany (IKF). In contrast to our earlier work, in these experiments emphasis was put on the second of the above mechanisms namely to influence the sheath potential at the extraction by structures with special dielectric properties. Two different types of dielectric structures, Tantalum-oxide and Aluminum oxide (the latter also being used for the MD-method) with contrastingly different electrical properties were mounted on the extraction electrode of the IKF-ECRIS, facing the plasma. For both structures an increase of the extracted ion beam currents for middle and high charge states by 60-80 % was observed. The method is able to be applied also to other ECR ion sources for increasing the extracted ion beam performances.
	Poster TUPOT014 [0.510 MB]

TUPOT015	Permanent Magnet ECRIS for the KEK Digital Accelerator	ECRIS, plasma, high-voltage, ion-source	150
	K.W. Leo, T. Adachi Sokendai, Ibaraki, Japan T. Arai, K. Koyama, M. Wake KEK, Ibaraki, Japan K. Okazaki Nippon Advanced Technology Co. Ltd., Ibaraki-prefecture, Japan K. Takayama TIT, Yokohama, Japan
	The existing KEK 500 MeV booster synchrotron is renovated into a digital accelerator (DA) capable of accelerating all species of ion [1]. The KEK-DA is an induction synchrotron employing no large injector. Its concept was demonstrated in 2006 using the 12 GeV proton synchrotron [2,3], where a proton bunch was accelerated with pulse voltages generated by a transformer instead of RF. In the KEK-DA, O, Ne, and Ar ions from the ECRIS embedded in the 200 kV high-voltage terminal (HVT) are directly injected into the ring though the low energy beam transport line. The permanent magnet ECRIS, in which a plasma is fired by x-band microwave pulses of 3 msec at 10 Hz, has been assembled at KEK. Its operational performance such as charge-state spectrum, emittance, and current is tested since the last year. In addition, the HVT with a voltage stabilizing circuit is being assembled now. Beam dynamical analysis from the cathode hall to the separation magnet, where possible charge-state ions are contaminated in the space-charge limit and beam focusing is realized through the Einzel lens and tandem acceleration gaps, is discussed as well as operational characteristics of the ECRIS. [1] K. Takayama et al., “All-ion Accelerator: an Injector-free Synchrotron”, J. of Appl. Phys. 101, 063304(2007). [2] K. Takayama et al., “Experimental Demonstration of the Induction Synchrotron”, Phys. Rev. Lett. 98, 054801 (2007). [3] K. Takayama and R.Briggs (Eds.), Induction Accelerators (Springer-Verlarg, 2010).
	Poster TUPOT015 [1.947 MB]

TUPOT016	Long-Term Operation Experience With Two ECR Ion Sources and Planned Extensions at HIT	ion-source, extraction, proton, linac	153
	T. Winkelmann, R. Cee, Th. Haberer, B. Naas, A. Peters HIT, Heidelberg, Germany
	The HIT (Heidelberg Ion Beam Therapy Center) is the first hospital-based treatment facility at a hospital in Europe where patients can be treated with protons and carbon ions. Since the commissioning starting in 2006 two 14.5 GHz electron cyclotron resonance ion sources are routinely used to produce a variety of ion beams from protons up to oxygen. The operating time is 330 days per year, our experience after three years of continuous operation will be presented. In the future a helium beam for patient treatment is requested, therefore a third ion source will be integrated. This third ECR source with a newly designed extraction system and a spectrometer line will be installed at a testbench to commission and validate this section. Different test settings are foreseen to study helium operation as well as enhanced parameter sets for proton and carbon beams in combination with a modified beam transport line for higher transmission efficiency. An outlook to the possible integration scheme of the new ion source into the production facility will be discussed.
	Poster TUPOT016 [4.294 MB]

TUPOT017	CEA/Saclay Light Ion Sources Status and Developments	plasma, ion-source, extraction, emittance	156
	R. Gobin, C.M. Mateo, S. Nyckees CEA/IRFU, Gif-sur-Yvette, France G. Adroit, G. Bourdelle, N. Chauvin, O. Delferrière, Y. Gauthier, P. Girardot, F. Harrault, C. Marolles, B. Pottin, Y. Sauce, F. Senée, O. Tuske, T.V. Vacher, C. Van Hille CEA/DSM/IRFU, France
	After several years of high intensity light ion beam production with the SILHI source, CEA Saclay is now involved in the construction of different injectors dedicated to large infrastructures like IFMIF or Spiral 2. Other installations are also interested by high intensity ion sources like ESS or FAIR. Such machines plan to produce and accelerate proton or deuteron beams in pulsed or continuous mode. The SILHI source, based on ECR plasma generation, already demonstrated its performance in both modes. As a consequence, at present time the construction of 2 new injectors for Spiral 2 and IFMIF (source and low energy beam lines) is in progress at CEA/Saclay. This article will report on the status of both installations. It will also point out on additional developments presently under progress for high intensity beam characterization or plasma production understanding. Such developments are mainly done with the new BETSI test bench operating for several months.
	Poster TUPOT017 [2.020 MB]

TUPOT018	Sheath Formation of a Plasma Containing Multiply Charged Ions, Cold and Hot Electrons, and Emitted Electrons	electron, plasma, resonance, ion-source	159
	H.J. You NFRI, Daejon, Republic of Korea
	A model of sheath formation was extended to a plasma containing multiply charged ions (MCIs), cold and hot electrons, and secondary electrons emitted either by MCIs or hot electrons. The present study was motivated by the fact that the secondary electron yields are strongly dependent on the charge state of the ions and on the incident energy of electrons. Therefore, the contributions of the secondary electron emissions on the sheath formation would be severe in ECRIS plasmas where the charge state of ions is high and highly energetic electrons exist. In the model, modification of the “Bohm criterion” was given; thereby the sheath potential drop and the critical emission condition were analyzed. The model calculations were made mainly on the effects of the emitted electrons on the variations of the sheath potential drop, the particle and heat flux to the wall, by which some explanations for the effect of secondary electrons in ECR ion sources are given.
	Poster TUPOT018 [0.259 MB]

WECOAK01	Characterization of the Microwave Coupling to the Plasma Chamber of the LBL ECR Ion Source.	plasma, cavity, coupling, ECR	162
	C.M. Lyneis, J.Y. Benitez, D. Leitner, J.D. Noland, M.M. Strohmeier LBNL, Berkeley, California, USA H. A. Koivisto, O.A. Tarvainen JYFL, Jyväskylä, Finland
	The characteristics of the microwave coupling of the 6.4 GHz ECR ion source were measured as a function of frequency, input power and time dependence. In addition the plasma diamagnetism and bremsstrahlung could be measured to help quantify the time dependence of the plasma build up and energy content. The LBL ECR plasma chamber, which has a diameter to wavelength ratio of 1.9 is not as over-moded as the 14 GHz AECR-U, which has a ratio greater than 3. This makes it possible to locate frequencies, where a single RF mode is predominately excited. For one of these modes we were able to demonstrate that with no plasma in the cavity, it is over-coupled and as the power is increased, the plasma density rises and the plasma loading increases it becomes under-coupled. By measuring the ratio of the incident to reflected power it is possible to show the microwave electric field levels saturate with increasing power. In the paper, the time dependence of the plasma loading and plasma diamagnetism as a function of input power and time are analyzed. The measurements of the plasma loading also provide insight into the dynamics of microwave heating in a multimode cavity.
	Slides WECOAK01 [1.593 MB]

WECOAK02	Some Considerations About Frequency Tuning Effect in ECRIS Plasmas	plasma, electron, simulation, resonance	165
	D. Mascali, G. Castro, L. Celona, G. Ciavola, N. Gambino, S. Gammino, R. Miracoli, L. Neri INFN/LNS, Catania, Italy F. Maimone GSI, Darmstadt, Germany
	During the last years many experiments have demonstrated that slight variations in microwave frequency used to heat and sustain the plasma of ECRIS may strongly influence their performances (frequency tuning effect) both in terms of extracted current and mean charge state. Theoretical investigations revealed that this phenomenon can be correctly explained assuming that the plasma chamber works as a resonant cavity: standing waves are excited inside of it, and their spatial structure considerably changes even with slight variations of the pumping frequency. Therefore some particular modes present a higher electric field on the resonance surface, that is the only region in which the energy transfer from waves to electrons occurs. Experimental measurements carried out on microwave discharge plasmas at high density (up to 10¹¹ cm^-3) featured that even if the absorption of electromagnetic energy at the ECR surface is evident, the stochastic nature of the wave-electron interaction allows the wave to be reflected at the extraction flange, thus forming a standing wave. The model here proposed, and based on PIC and MonteCarlo collisional simulations, puts in evidence that the frequency tuning effect in ECRIS has a global influence on plasma properties: it strongly affects both ion and electron dynamics. Electron heating, electron density distribution, ion formation and acceleration at resonance surface, beam formation are determined by the particular mode excited inside the cavity. This means that the frequency tuning will be an important tool for future ECRIS for the optimization of the beam quality (emittance, etc.).
	Slides WECOAK02 [4.765 MB]

WECOAK03	Studies of the ECR Plasma in the Visible Light Range	plasma, ECR, ECRIS, electron	168
	S. Biri, R. Rácz ATOMKI, Debrecen, Hungary J. Pálinkás DU, Debrecen, Hungary
	In order to investigate experimentally ECR plasmas one way is to record their optical spectra or photos in the infra-red, visible light (VL), ultra-violet or X-ray regions. The measurements and analysis of photos and spectra taken in any of these regions are usually affordable tasks. The non-destroying nature of this method is certainly an advantage, but the drawback is that the recorded information in most cases means integration over a specific line-of-sight in the plasma volume. Recently high resolution VL plasma photographs were taken at the ATOMKI-ECRIS using an 8 megapixel digital camera. Plasmas were generated from eight gases (He, methane, N, O, Ne, Ar, Kr, Xe) and from their mixtures. The analysis of the photo series gave us many qualitative and numerous valuable physical information on the nature of ECR plasmas [1, 2]. It is a further challenging task to understand the colors of this special type of plasmas. The colors can be determined by the VL electron transitions of the plasma atoms and ions. Through the examples of He and Xe we analyze the physical processes which effects the characteristic colors of these plasmas. [1] Rácz R., Biri S., Pálinkás J.: Electron cyclotron resonance plasma photos. Rev. Sci. Instrum. 81 (2010) 02B708. [2] Rácz R., Biri S., Pálinkás J.: ECR Plasma Photographs as Plasma Diagnostic. Submitted to Plasma Sources Science and Technology.
	Slides WECOAK03 [1.573 MB]

WECOAK04	Bremsstrahlung and Ion Beam Current Measurements With SuSI ECR Ion Source	plasma, radiation, collimation, extraction	171
	T. Ropponen, D.G. Cole, G. Machicoane, A. Stolz, L.T. Sun, L. Tobos NSCL, East Lansing, Michigan, USA
	The Superconducting Source for Ions (SuSI) at the National Superconducting Cyclotron Laboratory at Michigan State University is a fully superconducting 3rd generation ECR ion source. The axial magnetic field is generated by six solenoid magnets which allow to control the magnetic field characteristics, such as resonance locations, mirror ratios and magnetic field gradients, almost independently. In addition, a collimation scheme in the SuSI beam line after the analyzing magnet has been developed to optimize the ion beam production from the ion source within a given acceptance. These aspects make SuSI an excellent tool for ECRIS research and development. In this paper we will focus on the bremsstrahlung and ion beam current measurements where the gradient on the magnetic field is changed while keeping the Bmin and axial plasma length as constants. We will also show how the shift of the extraction side resonance location affects the extracted ion beam currents and radiation spectra and, finally, we will discuss about the effect of flatB mode with a modern superconducting ECR ion source on the ion beam production and radiation levels.
	Slides WECOAK04 [3.752 MB]

WECOBK01	Commissioning of the ECRIS Charge State Breeder at TRIUMF	ion-source, target, TRIUMF, background	178
	F. Ames, R.A. Baartman, P.G. Bricault, K. Jayamanna TRIUMF, Canada's National Laboratory for Particle and Nuclear Physics, Vancouver, Canada T. Lamy LPSC, Grenoble, France
	Radioactive isotopes produced at the ISOL facility ISAC at TRIUMF are usually extracted from the target ion source system as singly charged ions. If the mass of those ions exceeds A=30 their acceleration requires the breeding to highly charged ions. A modified version of an ECRIS charge breeder (14.5 GHz PHOENIX from Pantechnik) has been installed and a first on-line test resulting in the successful acceleration of ⁸⁰Rb¹⁴⁺ has been performed already in 2008. During the radioactive beam time periods of 2009 and 2010 further measurements with stable and radioactive ions from different target ion source combinations have been performed to fully commission the system. Breeding efficiencies of several percent in the maximum of the charge state distribution have been achieved. Detailed results will be presented.
	Slides WECOBK01 [1.230 MB]

WECOBK02	Recent Performance of the ANL ECR Charge Breeder	injection, plasma, ECR, extraction	181
	R.C. Vondrasek, A. Kolomiets, R.C. Pardo, R.H. Scott ANL, Argonne, USA
	Funding: This work was supported by the U.S. Department of Energy, Office of Nuclear Physics, under Contract No. DE-AC02-06CH11357. The construction of the Californium Rare Ion Breeder Upgrade (CARIBU), a new radioactive beam facility for the Argonne Tandem Linac Accelerator System (ATLAS), is nearing completion. The facility will use fission fragments, with charge 1+ or 2+, from a 1 Ci ²⁵²Cf source; thermalized and collected into a low-energy particle beam by a helium gas catcher. An existing ATLAS ECR ion source was modified to function as a charge breeder in order to raise the ion charge sufficiently for acceleration in the ATLAS linac. A surface ionization source or an RF discharge source provide beams for charge breeding studies. An achieved efficiency of 11.9% for ⁸⁵Rb¹⁹⁺, with a breeding time of 200 msec, and 15.6% for ⁸⁴Kr¹⁷⁺ has been realized. Both results are with the source operating with two RF frequencies (10.44 + 11.90 GHz). After modification to the injection side iron plug, the charge breeder has been operated at 50 kV, a necessary condition for the resolution of the isobar separator.
	Slides WECOBK02 [3.351 MB]

WECOBK03	Fine Frequency Tuning of the PHOENIX Charge Breeder Used as a Probe for ECRIS Plasmas	plasma, injection, ECR, ion-source	184
	T. Lamy, J. Angot, M. Marie-Jeanne, J. Médard, P. Sortais, T. Thuillier LPSC, Grenoble Cedex, France A. Galatà INFN/LNL, Legnaro (PD), Italy H. A. Koivisto, O.A. Tarvainen JYFL, Jyväskylä, Finland
	Fine frequency tuning of ECR ion sources is a main issue to optimize the production of multiply charged ion beams. The PHOENIX charge breeder operation has been tested in the range 13,75 - 14,5 GHz with an HF power of about 400 W. The effect of this tuning is analyzed by measuring the multi-ionization efficiency obtained for various characterized injected 1+ ion beams (produced by the 2.45 GHz COMIC source). The 1+/n+ method includes the capture and the multi ionization processes of the 1+ beam and may be considered as a plasma probe. The n+ spectra obtained could be considered, in first approach, as an image of the plasma of the charge breeder. However, in certain conditions it has been observed that the injection of a few hundreds of nA of 1+ ions (i.e.: Xe¹⁺) in the plasma of the charge breeder, is able to destroy the charge state distribution of the support gas (i.e.: up to 40 % of O⁶⁺ and O⁷⁺ disappears). The study of this phenomenon will be presented along with plasma potential measurements for various charge states. This study may help to understand the ECRIS creation (or destruction) of highly charged ions.
	Slides WECOBK03 [7.745 MB]

WECOBK04	Preliminary Results of Spatially Resolved ECR Ion Beam Profile Investigations	extraction, ion-source, ECR, ECRIS	188
	L. Panitzsch, M. Stalder, R.F. Wimmer-Schweingruber IEAP, Kiel, Germany
	The Department of Experimental and Applied Physics (IEAP) at the University of Kiel (CAU Kiel) is establishing a solar wind laboratory for the calibration of space instrumentation. The main item of this facility is a 11GHz (Plateau) ECR ion source. It can be operated at two different radial magnetic confinements, using a set of permanent magnets in either hexapole or dodekapole arrangement. While beam focussing by moving the extraction along the beam line to match the ion beam into the analysing magnet is well known, little is known about beam steering by moving the extraction in the plane perpendicular to the beam line. For the hexapole-configuration we will present our results about the feasibility of ion beam focussing and steering using a 3D-movable extraction. The beam profiles of these measurements will be recorded in comparatively high resolution with a Faraday cup array (see paper doi: 10.\|10\|63/1.3246787). This method will be shortly introduced within this talk, as well.
	Slides WECOBK04 [13.317 MB]

THCOAK01	A Correction Scheme for the Hexapolar Error of an Ion Beam Extracted from an ECRIS	simulation, plasma, extraction, emittance	191
	P. Spädtke, R. Lang, J. Mäder, F. Maimone, J. Roßbach, K. Tinschert GSI, Darmstadt, Germany
	The extraction of any ion beam from ECRIS is determined by the good confinement of such ion sources. It has been shown earlier, that the ions are coming from these places, where the confinement is weakest. The assumption that the low energy ions are strongly bound to the magnetic field lines require furthermore, that only these ions which start on a magnetic field line which go through the extraction aperture can be extracted. Depending on the setting of the magnetic field, these field lines may come from the loss lines at plasma chamber radius. Because the longitudinal position of these field lines depends on the azimuthal position at the extraction electrode, the ions are extracted from different magnetic flux densities. Whereas the solenoidal component is not curable, the hexapolar component can be compensated by an additional hexapole after the first beam line focusing solenoid. The hexapole has to be rotatable in azimuthal direction and moveable in longitudinal direction. For a good correction the beam needs to have such a radial phase space distribution, that the force given by this hexapole act on the aberrated beam exactly in such a way to create a linear distribution after that corrector.
	Slides THCOAK01 [1.115 MB]

THCOAK02	Kinetic Plasma Simulation of Ion Beam Extraction from an ECR Ion Source	simulation, ECR, electron, ion-source	194
	S.M. Elliott, E.K. White Thin Film Consulting, Longmont, Colorado, USA J. Simkin Vector Fields Ltd., Oxford, United Kingdom
	Designing optimized ECR ion beam sources can be streamlined by the accurate simulation of beam optical properties in order to predict ion extraction behavior. The complexity of these models, however, can make PIC-based simulations time-consuming. In this paper, we first describe a simple kinetic plasma finite element simulation of extraction of a proton beam from a permanent magnet hexapole electron cyclotron resonance (ECR) ion source. Second, we analyze the influence of secondary electrons generated by ion collisions in the residual gas on the space charge of a proton beam of a dual-solenoid ECR ion source. The finite element method (FEM) offers a fast modeling environment, allowing analysis of ion beam behavior under conditions of varying current density, electrode potential, and gas pressure.
	Slides THCOAK02 [0.821 MB]

THCOAK03	Dipole Magnet Optimization for High Efficiency Low Energy Beam Transport	emittance, simulation, ECRIS, extraction	197
	S. Saminathan, J.P.M. Beijers, S. Brandenburg, V. Mironov, J. Mulder KVI, Groningen, The Netherlands
	Losses in the low-energy beam transport line from KVI-AECRIS to AGOR cyclotron are estimated to be around 50%. Numerical simulations of the beam transport were performed using the tracing code LORENTZ-3D. It was found that most of the losses are due to second order optical aberrations in the 110-degree analyzing magnet. These aberrations result in an increase of the effective emittance in both horizontal and vertical directions. We will show that by suitably modifying the magnet pole surfaces the second-order aberrations can be compensated to a large extent resulting in a substantially lower effective emittance of the transported beam.
	Slides THCOAK03 [1.102 MB]

THCOAK04	Modeling ECRIS Using a 1D Multifluid Code	extraction, ECR, ion-source, instrumentation	200
	M. Stalder IEAP, Kiel, Germany
	We developed a one-dimensional (1D) multifluid code to simulate the production and the transport of multiple ion species in an electron cyclotron ion source (ECRIS). The ion species are assumed to be highly collisionally coupled. Each ion species is treated as a independent fluid. This allows us to study the influence of the ion temperature. The temperature is assumed to be equal for all charge states and in the whole ECRIS. As starting parameters we choose a hot magnetically trapped electron distribution, a cold electron distribution trapped by the plasma potential an the neutral density. Modeling the interaction of the different fluids led to a new understanding of the influence of the electrostatic potential that balances the pressure gradient of the ions species in the ECRIS. The highest charge states are not confined strongest as in the over barrier model but expelled in comparison to lower charge states. It can be shown that the relative velocity v of the treated fluids scales as v ~ T^5/3 with the ion temperature. First results of the simulations are presented together with a discussion of the modeling approach for the multifluid case and its theoretical predictions. As a baseline for our simulations we mainly used the results of the 1D GEM ECRIS fluid simulations.
	Slides THCOAK04 [2.268 MB]

THCOBK01	Concluding Remarks	ion-source, ECR, plasma, ECRIS	201
	T. Nakagawa RIKEN Nishina Center, Wako, Japan
	Concluding remarks kindly done by Takahide Nakagawa
	Slides THCOBK01 [0.436 MB]

Paper

Title

Other Keywords

Page

MOCOAK01

SECRAL Status and First Beam Test at 24GHz

ECR, heavy-ion, ion-source, plasma

1

H.W. Zhao, Y. Cao, Y.C. Feng, X.H. Guo, J.Y. Li, W. Lu, L.T. Sun, D. Xie, X.Z. Zhang, H. Zhao
IMP, Lanzhou, People's Republic of China

SECRAL has been in routine operation at 18GHz for HIRFL (Heavy Ion Research Facility in Lanzhou) accelerator complex since May 2007. It has delivered many highly charged heavy ion beams for the HIRFL accelerator and the total beam time so far has exceeded 3000 hours. To further enhance the SECRAL performance, a 24GHz/7kW gyrotron microwave amplifier has been installed and tested. Very exciting results were produced with quite a few new record highly-charged ion beam intensities. Bremstrahlung measurements at 24GHz have shown that X-ray is much stronger at higher RF frequency, higher RF power and higher minimum B field. Beam emittance study has been conducted in order to improve the beam brightness. An additional cryostat with five GM cryocoolers was installed atop the SECRAL to liquefy the boil-off helium gas to minimize the liquid helium consumption. The latest results and reliable long-term operation for the accelerator have once again demonstrated that SECRAL is one of the best performance ECR ion source for the production of highly-charged heavy ion beams. Detailed and future developments of SECRAL will be presented.

Slides MOCOAK01 [4.739 MB]

MOCOAK02

Intense Beam Production with SuSI

ECR, ion-source, ECRIS, plasma

4

L.T. Sun, J. Brandon, D.G. Cole, M. Doleans, G. Machicoane, D. Morris, T. Ropponen, L. Tobos
NSCL, East Lansing, Michigan, USA
E. Pozdeyev
FRIB, East Lansing, Michigan, USA

SuSI ion source, a 3rd generation fully superconducting ECR ion source is now used for injection into the Coupled Cyclotron Facility since September 2009. Initial performances during the commissioning of SuSI were mainly limited by the microwave power available from a single 18 GHz microwave amplifier, especially for the production of heavier ion beams. The Injection of SuSI was modified to add a second 18 GHz amplifier, to reach a maximum of 3.0 kW of RF power inside the plasma chamber. Production of heavy ion beams, such as Kr¹⁴⁺, Bi³⁰⁺ and U³³⁺ is reported, to demonstrate the performance of SuSI. Additional studies were made with various ion source parameters to optimize the beam intensity within a normalized emittance of 0.9pi.mm.mrad as needed for the FRIB project and will be reported in this paper.

Slides MOCOAK02 [1.672 MB]

MOCOAK03

Status of RIKEN SC-ECRIS

ECR, ion-source, ECRIS, heavy-ion

8

T. Nakagawa, Y. Higurashi, J. Ohnishi
RIKEN Nishina Center, Wako, Japan
T. Aihara, M. Tamura
SHI Accelerator Service Ltd., Tokyo, Japan

To increase the beam intensity of highly charged heavy ions for RIKEN RIBF project, we constructed and tested RIKEN new SC-ECRIS. After obtaining the first beam in the spring of 2009, we tried to optimize the ion source condition for maximizing the beam intensity with 18GHz microwave. In this experiment, we intensively studied the effect of the magnetic field gradient and ECR zone size on the beam intensity. In this experiment, it was clearly seen that the gentler field gradient and lager ECR zone size give higher beam intensity. Based on these studies, we produced 550μA of Ar¹¹⁺ and 350μA of Ar¹²⁺ at the RF power of 1.8kW. In this summer, we will try use the 28GHz microwaves to increase the beam intensity. In this contribution, we present the structure of the SC-ECRIS and the results of test experiments with 18 GHz microwave in detail. We also present the future plan to increase the beam intensity.

Slides MOCOAK03 [2.366 MB]

MOCOAK04

Status of the VENUS ECR Ion Source

ion-source, ECR, plasma, cyclotron

11

D. Leitner, P. Ferracin, A. Hodgkinson, M. Leitner, T.J. Loew, C.M. Lyneis, G.L. Sabbi
LBNL, Berkeley, California, USA
G. Machicoane, E. Pozdeyev
NSCL, East Lansing, Michigan, USA

The fully superconducting 28-GHz VENUS ECR ion source serves as prototype injector for the Facility for Rare Isotope Beams (FRIB) project at Michigan State University (MSU) as well as injector ion source for the 88-Inch Cyclotron at Lawrence Berkeley National Laboratory (LBNL). As such the source has produced many record beams of high charge state as well as high-intensity, medium charge state ions. As the FRIB project has now entered the preliminary design phase, Lawrence Berkeley National Laboratory is involved in the design of two new VENUS-like ECR injector ion sources for the FRIB facility. This paper will review the requirements for the FRIB injector, and present VENUS cryostat design changes which will allow installation on a 100 kV platform. In addition, a possible future upgrade path for the FRIB injector using an advanced Nb3Sn magnet structure is described. In 2008, at LBNL the VENUS ECR ion source experienced a major setback when one of the sextupole leads evaporated during a quench caused by a low liquid helium level in the cryostat. The repair process and the long reconstruction effort as well as the status of the reinstallation will be described.

Slides MOCOAK04 [4.180 MB]

MOCOBK01

ECR Ion Sources for the Facility for Rare Isotope Beams (FRIB) Project at Michigan State University

ion-source, ECR, linac, emittance

14

G. Machicoane, M. Doleans, O.K. Kester, T. Ropponen, L.T. Sun, X. Wu
NSCL, East Lansing, Michigan, USA
D. Leitner
LBNL, Berkeley, California, USA
E. Pozdeyev, E. Tanke
FRIB, East Lansing, Michigan, USA

Funding: Work supported by US DOE Cooperative Agreement DE-SC0000661
Once operational, the Facility for Rare Isotope Beams (FRIB) will open the possibility to gain key understanding in nuclear science and in particular regarding the properties of nuclei far from the valley of stability or the nuclear processes in the universe. In addition it will also allow experimenters to test fundamental symmetries. The production of rare isotopes with FRIB will be achieved, using a heavy ion driver linac that will accelerate a stable isotope beam to 200 MeV/u and deliver it on a fragmentation target. FRIB aims to reach a primary beam power of 400 kW for light to heavy elements up to Uranium. To meet the intensity requirement two high performance ECR ion sources operating at 28 GHz will be used to produce high intensity of medium to high charge state ion beams. Plans regarding initial beam production with the ECR ion sources and beam transport through the front end will be discussed.

Slides MOCOBK01 [3.259 MB]

MOCOBK02

Present Status of FLNR (JINR) ECR Ion Sources

ion-source, cyclotron, ECR, injection

17

S.L. Bogomolov, V.B. Bekhterev, V.M. Drobin, A. Efremov, B. Gikal, G.G. Gulbekyan, Yu.K. Kostyukhov, N. Lebedev, V.N. Loginov, V.V. Seleznev, Yu. Yazvitsky
JINR, Dubna, Moscow Region, Russia

Six ECR ion sources have been operated in the Flerov Laboratory of Nuclear Reactions (JINR). Two 14 GHz ECR ion sources (ECR4M and DECRIS-2) supply various ion species for the U400 and U400M cyclotrons correspondingly for experiments on the synthesis of heavy and exotic nuclei using ion beams of stable and radioactive isotopes. The 18 GHz DECRIS-SC ion source with superconducting magnet system produce ions from Ar up to W for solid state physics experiments and polymer membrane fabrication at the CI-100 cyclotron. The third 14 GHz ion source DECRIS-4 with “flat” minimum of the axial magnetic field is used as a stand alone machine for test experiments and also for experiments on ion modification of materials. The other two compact ECR ion sources with all permanent magnet configuration have been developed for the production of single charged ions and are used at the DRIBs installation and at the MASHA mass-spectrometer. In this paper, present status of the ion sources, recent developments and plans for modernization are reported. Also the results of the preliminary test of the DECRIS-SC2 ECR source will be presented.

Slides MOCOBK02 [11.671 MB]

MOCOBK03

Status of Ion Sources at HIMAC

ion-source, ECR, plasma, radiation

20

A. Kitagawa, M. Muramatsu, Y. Sakamoto
NIRS, Chiba-shi, Japan
S. Biri
ATOMKI, Debrecen, Hungary
A.G. Drentje
KVI, Groningen, The Netherlands
T.F. Fujita
National Institute of Radiological Sciences, Chiba, Japan
T. Sakuma, N. Sasaki, T. Sasano, W. Takasugi
AEC, Chiba, Japan

Since 1994, heavy-ion radiotherapy using carbon ions is successfully carried out with the Heavy Ion Medical Accelerator in Chiba (HIMAC) at the National Institute of Radiological Sciences (NIRS). Over 5000 cancer patients have already been treated with 140-400 MeV/u carbon beams. These clinical results have clearly verified the advantages of carbon ion. The ion source needs to realize a stable beam with the same conditions for daily operation. Maintenance is restricted to once per year. However, the deposition of carbon on the wall of the plasma chamber is normally unavoidable. This causes an ‘anti-wall-coating effect’, i.e. a decreasing of the beam (typically 50 % after a few months of operation), especially for the higher charge-state ions due to the surface material of the wall. The ion source has - even in this bad condition – still to produce a sufficiently intense and stable beam. We summarize our experience during 16 years of operation and show the scope for further developments. HIMAC is dedicated to radiotherapy, but it has as a second essential task to operate as a facility for physicist users. In that scope it accelerates many ion species for basic experiments. In order to serve all HIMAC users at best, the extension of the range of ion species is an important subject in ion source development. For example, in order to increase the ECRIS-beam intensity for heavier ions, microwave is applied at different frequencies by a traveling wave tube amplifier and….?

Slides MOCOBK03 [2.780 MB]

MOCOBK04

Recent Activities at the ORNL Multicharged Ion Research Facility (MIRF)

ECR, plasma, electron, permanent-magnet

23

F.W. Meyer, M.E. Bannister, S. Deng, I.N. Draganić, J.W. Hale, P.R. Harris, C.C. Havener, H.F. Krause, C.R. Vane
ORNL, Oak Ridge, Tennessee, USA

Funding: Sponsored by the Office of Fusion Energy Sciences and the Office of Basic Energy Sciences of the U.S. DOE under contract No. DE-AC05-00OR22725 with UT_Battelle.
We report on recent upgrades of the ORNL Multicharged Ion Research Facility, and our activities in the area of ECR ion source diagnostic measurements. The upgrades include installation of a new all permanent magnet ECR ion source [1] on a high voltage platform that increases our high energy beam production capability to 250keV/q, and installation of a floating beamline fed by a 10 GHz CAPRICE ECR ion source for producing decelerated ion beams to energies as low as a few eV/q range. The primary application of all the produced ion beams is to study fundamental collisional interactions [2] of multicharged ions with electrons, atoms, and surfaces. We also summarize recent diagnostic measurements of the ECR plasma potential and other plasma parameters using an in-situ Langmuir probe installed in the ECR edge plasma and complementary measurements [3] using an external beam deceleration method.
[1] D. Hitz et al. , “An All-Permanent Magnet ECR Ion Source for the ORNL MIRF Upgrade Project,” AIP Conference Proceedings 749, 123 (2005), Woodbury, NY.
[2] F.W. Meyer, “ECR-Based Atomic Collision Physics Research at ORNL MIRF,” in Trapping Highly Charged Ions: Fundamentals and Applications, J. Gillaspy, ed., Nova Science Pub., New York, 2000, pp. 117-164.
[3] P.R. Harris and F.W. Meyer, Rev. Sci. Inst. 81, 02A310 (2010).

Slides MOCOBK04 [2.645 MB]

MOCOCK01

PK-ISIS: a New Superconducting ECR Ion Source at Pantechnik

permanent-magnet, extraction, ECR, ion-source

26

A.C.C. Villari, C. Bieth, W. Bougy, B.N. Brionne, X. Donzel, G. Gaubert, R. Leroy, A. Sineau, O. Tasset, C. Vallerand
PANTECHNIK, BAYEUX, France
T. Thuillier
LPSC, Grenoble, France

The new ECR ion source PK-ISIS was recently commissioned at Pantechnik. Three superconducting coils generate the axial magnetic field configuration while the radial magnetic field is done with multi-layer permanent magnets. Special care was devoted in the design of the hexapolar structure, allowing a maximum magnetic field of 1.32 T at the wall of the 82 mm diameter plasma chamber. The three superconducting coils using Low Temperature Superconducting wires are cooled by a single double stage cryo-cooler (4.2 K). Cryogen-free technology is used, providing reliability, easy maintenance at low cost. The maximum installed RF power (18.0 GHz) is of 2 kW. Metallic beams can be produced with an oven (Tmax = 1400 °C) installed with an angle of 5° with respect to the source axis or a sputtering system, mounted in the axis of the source. The beam extraction system is constituted of three electrodes in accel-decel configuration. Description of the source and results of the magnetic measurements will be given. Performances of the source in terms of beam intensities and charge states distribution will be presented.

Slides MOCOCK01 [3.226 MB]

MOCOCK02

3D Simulation Studies and Optimization of Magnetic Holes of HTS-ECRIS for Improving the Extraction Efficiency and Intensities of Highly Charged Ions

plasma, ECR, extraction, ion-source

27

G. Rodrigues, R.N. Dutt, D. Kanjilal, P.S. Lakshmy, Y. Mathur, U.K. Rao, A. Roy
IUAC, New Delhi, India
R. Baskaran
IGCAR, Channai, India

3D simulation studies using RADIA code have been performed to optimise the magnetic holes in high temperature superconducting electron cyclotron resonance (HTS-ECRIS) ion source for improving the extraction efficiency and intensities of highly charged ions. The magnetic field improvements using simple techniques like optimisation of iron regions is found to be economical. The extraction efficiency can be increased three-fold in the case of a hexapole magnet depending on the level of the uniformity of the fields in the high and low regions. This technique further minimises localized heating of the plasma chamber walls which can improve the vacuum conditions in an ECR ion source. For superconducting sources where the x-ray heat load poses severe problems during operation, such a reduction of heating load is of great significance. The typical triangular pattern of the plasma impact observed on the plasma electrode of HTS ECRIS at various tuning conditions are reproduced by the simulations. Details of the simulations and experimental results will be presented.

Slides MOCOCK02 [2.925 MB]

MOCOCK03

Design Study of a Higher Magnetic Field SC ECRIS at IMP

ECRIS, plasma, solenoid, sextupole

30

D. Xie, W. Lu, X.Z. Zhang, H.W. Zhao
IMP, Lanzhou, People's Republic of China

Development of ECR ion source has demonstrated that, as the empirical scaling laws summarized, higher magnetic field with higher operation frequencies will greatly improve the source performance. Based on the great success of SECRAL, a higher magnetic field SC ECRIS is planned to meet the new accelerator demands at IMP. However, there are many practical issues in the design and construction of a higher field SC ECRIS that need to be addressed. In this paper we will present and discuss the design features of the higher field SC ECR with a maximum axial field of 7.0 T and a radial field of 3.5 T at the plasma chamber inner surface, and operating frequency up to 50 GHz.

Slides MOCOCK03 [1.825 MB]

MOCOCK05

Multigan®: a New Multicharged Ion Source Based on Axisymetric Magnetic Structure

ECRIS, plasma, electron, extraction

37

L. Maunoury, P. Delahaye, M. Dubois, P. Jardin, P. Lehérissier, M. Michel, J.Y. Pacquet
GANIL, Caen, France
S. Biri
ATOMKI, Debrecen, Hungary
X. Donzel, G. Gaubert, R. Leroy, A.C.C. Villari
PANTECHNIK, BAYEUX, France
C. Pierret
CIMAP, Caen, France

Standard ECR ion sources have radial magnetic field created by a multi-pole, e.g. hexapole or higher order, which fills all space in the center of the source structure. Based on the Monogan® ECRIS [1] concept, a new multicharged ECR ions source has been designed with a large opening space in the center of the source structure. This particular design allows, in a first approach, direct radial contact with the ECR plasma, allowing positioning of probes and targets for radioactive beam production very close to the plasma region. Secondly, the absence of a multi-pole allows considering extremely high magnetic fields with significantly smaller structural constraints. This source is combining the advantages of the axisymetric magnetic feature of Monogan® with higher frequencies. This paper will describe the magnetic structure calculation as well as the mechanical design and stresses of a full permanent magnet ion source using this concept. This source will be the first prototype of such an ECR ion source. Finally, using TrapCad code [2], an estimation of the electronic energy distribution has been calculated and thus, the performance of the source has been deduced. The beam formation and extraction were also roughly calculated taking into account magnetic and electric fields.
[1] P. Jardin et al., Review of Scientific Instruments, 73, 789 (2002).
[2] L. Maunoury et al., Plasma Sources Science and Technology , 18, 015019 (2009).

Slides MOCOCK05 [5.532 MB]

MOPOT001

Operation of KeiGM for the Carbon Ion Therapy Facility at Gunma University

extraction, heavy-ion, ion-source, vacuum

40

M. Muramatsu, S. Hojo, A. Kitagawa
NIRS, Chiba-shi, Japan
Y. Kijima
Mitsubishi Electric Corp., Energy & Public Infrastructure Systems Center, Kobe, Japan
H. Miyazaki, K. Sawada, T. Ueno
SHI, Ehime, Japan
K. Torikai, S. Yamada
Gunma University, Heavy-Ion Medical Research Center, Maebashi-Gunma, Japan
M. Tsuchiyama, S. Ueda
Mitsubishi Electric Corp., Energy Systems Centre, Kobe, Japan

Carbon-ion radiotherapy has been carried out at Gunma University Heavy Ion Medical Centre (GHMC) since March 2010. A compact ECR ion source for GHMC, so-called KeiGM, supplies C⁴⁺ ions for treatment. A microwave source with the traveling-wave-tube was adopted for KeiGM, with a frequency range and maximum power of 9.75 - 10.25 GHz and 750 W, respectively. KeiGM was operated from March to May 2010 for the clinical trial without any trouble and maintenance. KeiGM supplied the carbon ions from 7:30 in the morning to 0:00 midnight on weekdays. Sometimes it was operated for the beam tuning of accelerator on Saturday and Sunday too. The operation time of KeiGM for two months was about 780 hours. Although the beam intensity decreased by 20% at first, it has been constant for the last two months. The beam intensity of C⁴⁺ was 200 euA at 30 kV extraction in May 2010. The fluctuation of beam intensity was less than 10%. The operation parameters were as follows; the microwave frequency and power were 10.042 GHz and 300 W, respectively. CH4 gas was fed, and the gas flowrate was 0.054 cc/min. The extraction voltage was 30 kV. The repetition frequency and pulse width were 0.36 Hz and 50 msec, respectively. Gunma University has successfully treated the first 12 patients for the clinical trial, thus the Japanese Ministry of Health and Labor Welfare approved GHMC as “advanced medicine”. We will report the operation of KeiGM and the status of their daily treatment.

Poster MOPOT001 [2.685 MB]

MOPOT002

Two-Chamber Configuration of the Bio-Nano ECRIS

plasma, ECRIS, extraction, resonance

43

T. Uchida, H. Minezaki, Y. Yoshida
Toyo University, Kawagoe-shi, Saitama, Japan
T. Asaji, K. Tanaka
Tateyama Machine Co. Ltd., Toyama-shi, Japan
S. Biri, R. Rácz
ATOMKI, Debrecen, Hungary
Y. Kato
Osaka University, Graduate School of Engineering, Osaka, Japan
A. Kitagawa, M. Muramatsu
NIRS, Chiba-shi, Japan

The Bio-Nano ECRIS was designed for new materials production on nano-scale [1]. Our main target is the endohedral fullerene, which have potential in medical care, biotechnology and nanotechnology. In particular, iron-encapsulated fullerene can be applied as a contrast material for magnetic resonance imaging or microwave heat therapy. There are several promising approaches to produce the endohedral fullerenes using an ECRIS. One of them is the ion-ion collision reaction of fullerenes and aliens ions to be encapsulated in the mixture plasma of them. Another way is the shooting of ion beam into a pre-prepared fullerene layer. In this study, the new device configuration of the Bio-Nano ECRIS is reported which allows the application of both methods. The plasma chamber is divided into two chambers by installing mesh electrodes. In the gas injection-side 1st chamber at 2.45 GHz plasmas (N₂, Ar, He, Fe,) are produced on the usual way. These ions then are extracted to the 2nd chamber where an evaporation boat for fullerene is installed. The fullerene neutrals can be ionized (using 10 GHz in the 2nd chamber) and are deposited on a large plasma electrode where they are continuously irradiated by the ions from the 1st chamber. The ions produced either in the 1st or 2nd chamber can be in-situ extracted and analyzed. The basic concept and the preliminary results using Ar gas and N₂ gas plasmas will be presented.
[1] T. Uchida et al., Proc. ECRIS08, Chicago, USA, pp. 27-31 (2008)

Poster MOPOT002 [6.248 MB]

MOPOT003

Study of Potential Application of Compact ECRIS to Analytical System

ECR, ion-source, plasma, permanent-magnet

46

M. Kidera
RIKEN Nishina Center, Wako, Japan
S. Enomoto
Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan
S. Kishi, Y. Seto
National Research Institute of Police Science, Chiba, Japan
T. Nagamatsu, T. Tanaka
Tokyo University of Science, Faculty of Engineering Division I, Tokyo, Japan
K. Takahashi
RIKEN, Saitama, Japan

A place of an activity of ECR ion sources is not only ion source on a heavy ion accelerator facility. A highly ionization efficiency, flexibility of ionized sample, low consumption rate in sample, and non-equilibrium ECR plasma, etc. that a ECR ion source have, may be needed in other fields at time. We have developed several kinds of small ECRISs that have customized for the analysis. The purposes of the analysis are, precise measurement of isotope ratio of a metal element, detection of chemical warfare agents, and detection of produced molecular (or fragment) ions by the ECR plasma. In this workshop, we will report the compact ECRISs by a permanent magnet type for the analytical system.

Poster MOPOT003 [3.320 MB]

MOPOT004

Neutralisation of Accelerated Ions and Detection of Resulting Neutrals

ion-source, ECR, simulation, acceleration

49

T. Peleikis, L. Panitzsch, M. Stalder
IEAP, Kiel, Germany

At the University of Kiel, the Department of Experimental and Applied Physics is running an ECR ion source in order to, amongst others, calibrate space instruments designed to measure solar wind properties and suprathermal particles. The ion source is able to produce medium to highly charged ions which are then accelerated by an electrostatic field up to 400keV per charge. In order to extend the particle spectrum from ions to neutral atoms we are planning to install a device for the beam particle neutralisation. It will be used to calibrate instruments which measure neutral particles. This device will be located downstream from the sector magnet and the acceleration-stage. The sector magnet separates the ions by their m/q ratio. This way the type and the energy of the ions can be determined before the neutralisation. Neutralisation can be achieved either by passing the ions through a thin carbon foil (thickness ~88nm) or through a gastarget (thickness ~6mm, pressure ~0.1mbar) where charge-exchange occur. The remaining ions behind the neutraliser will be suppressed by an electrostatic separator. Both methods will alter the beam properties and lead to a divergence in energy and an angular spread of the beam. Simulations regarding these effects will be discussed. The overall progress on this project will be presented.

Poster MOPOT004 [1.776 MB]

MOPOT005

High Current Production with 2.45 GHz ECR Ion Source

extraction, ECR, ion-source, plasma

50

A. Coly, T. Lamy, T. Thuillier
LPSC, Grenoble Cedex, France
G. Gaubert, A.C.C. Villari
PANTECHNIK, BAYEUX, France

A new test bench has been installed at LPSC dedicated to 2.45 GHz ECR Ion Sources characterization. Several magnetic structures have been tested around the same plasma cavity. For example, a current density of 70 mA/cm² has been measured with the MONO1000 source lent by GANIL. An original ECRIS, named SPEED (for 'Source d'ions à aimants PErmanents et Extraction Dipôlaire'), presenting a dipolar magnetic field at the extraction will also be presented.

Poster MOPOT005 [3.130 MB]

MOPOT006

Ionization Efficiency of a COMIC Ion Source Equipped With a Quartz Plasma Chamber

plasma, ion-source, target, injection

51

P. Suominen, T. Stora
CERN, Geneva, Switzerland
J. Médard, P. Sortais
LPSC, Grenoble, France

The ISOLDE facility at CERN produces a wide range of radioactive ion beams due to a long history on target and ion source development. Because the radioactive isotope production is very limited, the most important ion source parameters are high ionization efficiency, selectivity and reliable operation under intense radiation. Currently used ion sources (mainly laser (RILIS [1]) and arc discharge -type ion sources (VADIS [2]) do not efficiently ionize light noble gases, such as helium, and molecules, such as CO, N₂ and NO. These beams were previously planned to be produced with 1+ ECR ion sources operating at 2.45 GHz (for example MINIMONO [3]) but due to new and more efficient RF coupling of COMIC-type ion sources [4], we expect to advance in 2.45 GHz ECRIS utilization for radioactive beam production. The new COMIC source designed by LPSC, Grenoble incorporates special features such as a plasma chamber fully made of quartz (Q-COMIC). This should provide chemically good conditions for molecular ion beam production, especially for carbon. This paper presents the first ionization efficiency measurements of the Q-COMIC.
[1] V.N. Fedosseev, et al, Nucl. Instrum. Methods Phys. Res. B 266/19-20 (2008) 4378.
[2] PhD thesis, univ. polyt. Bucarest, L. Penescu (2009).
[3] F. Wenander, W. Farabolini, G. Gaubert, P. Jardin, J. Lettry, Nucl. Phys. A, 746 (2004) 659.
[4] P. Sortais, T. Lamy, J. Médard, J. Angot, L. Latrasse, and T. Thuillier, Rev. Sci. Instrum. 81 (2010) 02B314.

Poster MOPOT006 [0.697 MB]

MOPOT008

He²⁺ Source Based on Penning Discharge with Additional 75 GHz ECR Heating

plasma, ECR, radiation

54

A. Vodopyanov, S. Golubev, I. Izotov, A. Mansfeld
IAP/RAS, Nizhny Novgorod, Russia
G. Yushkov
Institute of High Current Electronics, Tomsk, Russia

It is well known that one can reach high average charge of ions in the ECR plasma by increasing plasma density and decreasing neutral gas pressure. ECR discharge could be realized at very low gas pressure, but discharge startup takes longer time when gas pressure is low. So, it is impossible to realize ECR discharge with limited microwave heating pulse duration at gas pressure lower certain threshold value. This problem could be solved with help of trigger plasma, which should be ignited at low gas pressure in the trap with high magnetic field. This fore plasma could help to decrease ECR plasma startup time significantly and make it possible to realize ECR plasma at very low pressure in pulse operation regime. We suggest penning type discharge as a trigger discharge for fast startup of pulsed ECR plasma. Penning type discharge glows at as low pressure as needed. Discharge was realized in the simple mirror magnetic trap at pressure about 10^-5 mbar. Helium was used as an operating gas. Significant plasma density (about 10¹¹ cm^-3) was obtained at the moment just before microwave heating pulse started. Gyrotron radiation with frequency of 75 GHz, microwave power up to 200 kW and pulse duration up to 1 ms, was used for plasma heating. In the present work the fully striped helium ions were demonstrated, average charge of ions in the plasma was equal 2. Temporal evolution of charge state distribution was investigated. Charge state distribution over helium pressure was also studied.

Poster MOPOT008 [0.535 MB]

MOPOT010

The Light Ion Guide CB-ECRIS Project at the Texas A&M University Cyclotron Institute

ECRIS, cyclotron, light-ion, plasma

55

G. Tabacaru
Texas A&M University, Cyclotron Institute, College Station, USA
J. Ärje
JYFL, Jyväskylä, Finland
D.P. May
Texas A&M University Cyclotron Institute, College Station, Texas, USA

Texas A&M is currently configuring a scheme for the production of radioactive-ion beams that incorporates a light-ion guide (LIG) coupled with an ECRIS constructed for charge-boosting (CB-ECRIS). This scheme is part of an upgrade to the Cyclotron Institute and is intended to produce radioactive beams suitable for injection into the K500 superconducting cyclotron. The principle of operation is the following: a primary beam from the K150 cyclotron interacts with a production target placed in the gas cell. A continuous flow of helium gas maintains a constant pressure of 500 mbar maximum in the cell. Recoils are thermalized in the helium buffer gas and ejected from the cell within the gas flow through a small exit hole. The positively charged recoil ions (1+) are guided into a 2.5 m long, rf-only hexapole and will be transported in this manner on-axis into the CB-ECRIS. The CB-ECRIS operates at 14.5 GHz and has been specially constructed by Scientific Solutions of San Diego, California for charge-boosting. An overview of the entire project will be presented with details on different construction phases. Specific measurements and results will be presented as well as future development plans.

Poster MOPOT010 [12.413 MB]

MOPOT013

MONOBOB II : Latest Results of Monocharged Ion Source for SPIRAL2 Project

target, ECRIS, plasma, vacuum

64

M. Dubois, O. Bajeat, C. Barue, C. Canet, M. Dupuis, J.L. Flambard, R. Frigot, P. Jardin, C. Leboucher, N. Lecesne, P. Lecomte, P. Lehérissier, F. Lemagnen, L. Maunoury, O. Osmond, J.Y. Pacquet, A. Pichard
GANIL, Caen, France

MONOBOB II is an electron cyclotron resonance ion source (ECRIS) based on a cylindrical symmetry magnetic structure [1]. It has been designed for the SPIRAL2 project in order to ionize radioactive gases coming from the production targets of the Target Ion Source System (TISS). The goal is to build a long-lived ECRIS with the aim of running three months in the hostile environment of the production target while keeping high ionization efficiencies. The Target Ion Source System has been tested using noble gases (He, Ne, Ar, Kr and Xe), with and without target in order to observe the behavior of the source coupled to the target. Currently, the target is made of ~1000 carbon slices, having the same geometry as the final UCx target. So far, its temperature has been limited to 1500°C. Ionization efficiencies and response times of the TISS have been measured versus gases and target temperature [2]. Results should lead to determine the maximum radioactive ion production which can be reasonably expected with the final TISS. The status of this development will be presented.

Poster MOPOT013 [0.858 MB]

MOPOT014

The Design of 28 GHz ECR Ion Source for the Compact Linear Accelerator in Korea

ECRIS, ion-source, extraction, ECR

67

M. Won, B.S. Lee
Korea Basic Science Institute, Busan, Republic of Korea

The construction of a compact linear accelerator is in progress by Korea Basic Science Institute. The main capability of this facility is the production of multiply ionized metal clusters and the generation more intense beams of highly charged ions for material, medical and nuclear physical research. To produce the intense beam of highly charged ions, we will construct an Electron Cyclotron Resonance Ion Source (ECRIS) using 28 GHz microwaves. For this ECRIS, The design of a superconducting magnet, microwave inlet, beam extraction and plasma chamber was completed. Also we are constructing a superconducing magnet system. In this presentation, we will report the current status of development of our 28 GHz ECRIS.

Poster MOPOT014 [3.823 MB]

MOPOT015

The Design Study of Superconducting Magnet System for an Advanced ECR Ion Source

superconducting-magnet, ECRIS, ion-source, ECR

68

B.S. Lee, M. Won
Korea Basic Science Institute, Busan, Republic of Korea

Funding: This work was supported by KBSI grant (D30300) to M.S.Won
The Korea Basic Science Institute is developing a superconducting magnet system for 28 GHz Electron Cyclotron Resonance Ion Souce (ECRIS). We are invetigating in order to realize compact size, economic operation and generation of high current beam. Although companies and researchers have valuable experience, skill and ability in designing of superconducting magnet for ECRIS, they did not exactly proposed a excellent superconducting magnet system for ECRIS because many superconducting magnets were not required. Of course they do if we requried many magnets for the various appliation of ECRIS. In this presentation, we have filed reports of former reseacher and we have discussed the realization of ECRIS over 35 GHz.

Poster MOPOT015 [7.135 MB]

MOPOT016

A Low Power Survey of Radial-Offset Axial Sputtering and High Intensity Uranium Production from Axial Sputtering in SuSI

target, plasma, injection, survey

69

D.G. Cole, G. Machicoane, T. Ropponen, L.T. Sun, L. Tobos
NSCL, East Lansing, Michigan, USA

Prototype sputtering hardware has been tested in the SuSI ion source and early uranium ion production is discussed. Also, results of a low power survey of axial sputtering, to test sputtering efficiency at incremental radial offsets from on axis position, is reported.

Poster MOPOT016 [2.672 MB]

MOPOT017

Tests of a New Axial Sputtering Technique in an ECRIS

plasma, ECRIS, ECR, injection

72

R.H. Scott, R.C. Pardo, R.C. Vondrasek
ANL, Argonne, USA

Funding: This work is supported by the U.S. Department of Energy, Office of Nuclear Physics, under contract No. DE-AC02-06CH11357.
Axial and radial sputtering techniques have been used over the years to create beams from an ECRIS at multiple accelerator facilities. Operational experience has shown greater beam production when using the radial sputtering method versus axial sputtering. At Argonne National Laboratory, previous work with radial sputtering has demonstrated that the position of the sputter sample relative to the plasma chamber wall influences sample drain current, beam production and charge state distribution. The possibility of the chamber wall acting as a ground plane which influences the sputtering of material has been considered, and an attempt has been made to mimic this possible ground plane effect with a coaxial sample introduced from the injection end. Results of these tests will be shown as well as comparisons of outputs using the two methods.

Poster MOPOT017 [1.506 MB]

TUCOAK01

First A/Q=3 Beams of Phoenix V2 on the Heavy Ions Low Energy Beam Transport Line of SPIRAL2

ion-source, ECRIS, dipole, heavy-ion

75

C. Peaucelle
IN2P3 IPNL, Villeurbanne, France
J. Angot, P. Grandemange, T. Lamy, T. Thuillier
LPSC, Grenoble Cedex, France
J.-L. Biarrotte
IPN, Orsay, France
D. Uriot
CEA/DSM/IRFU, France

The heavy ions low energy beam transport line (LEBT) of Spiral2 built at LPSC Grenoble is fully operational since the beginning of 2010. This LEBT has been calculated and designed to hold permanently 15 mA of multicharged ions extracted from the source at 60 kV. PHOENIX V2 ECRIS is presently installed on the LEBT and first tests started few months ago: A reliable beam of 1 mAe of O⁶⁺ beam at 45 kV has already been obtained for a long period with a very good transmission, and good reproducibility. Tests continue with an optimization of Ar¹²⁺ beam performance. The promising results of these first runs, particularly emittance measurements, profiles and optimization of charge optics will be presented along. The ECRIS Phoenix V2 and different equipments installed on this line (vacuum system, optic elements, diagnostics) will be described. The future program and planned improvements on the LEBT will be also discussed in this paper.

Slides TUCOAK01 [2.402 MB]

TUCOAK02

Trace Space Reconstruction From Pepperpot Data

emittance, simulation, beam-transport, ECRIS

78

H.R. Kremers, J.P.M. Beijers, S. Brandenburg, V. Mironov, J. Mulder, S. Saminathan
KVI, Groningen, The Netherlands

We use a pepperpot emittance meter to determine the full transverse trace-space distribution of low-energy ion beams. One of the problems encountered with our emittance meter is that the correlation between the measured ion images and the holes in the pepperplate is somewhat ambiguous caused by the convoluted character of the trace-space distribution. In this paper we describe a method to solve this problem and illustrate it with measurements of the 4d transverse trace-space distribution behind the analyzing magnet of a 21 keV He¹⁺ beam extracted from the KVI-AECR ion source. From these measurements together with ion-transport simulations we conclude that second-order aberrations in the analyzing magnet cause a significant increase in the effective beam emittance.

Slides TUCOAK02 [3.474 MB]

TUCOAK03

Plasma-to-Target WARP Simulations of Uranium Beams Extracted from VENUS Compared to Emittance Measurements and Beam Images

simulation, extraction, ion-source, emittance

81

D. Winklehner, J.Y. Benitez, D. Leitner, M.M. Strohmeier, D.S. Todd
LBNL, Berkeley, California, USA
D.P. Grote
LLNL, Livermore, California, USA

The superconducting ECR ion source VENUS was built as injector for the 88-Inch Cyclotron at Lawrence Berkeley National Laboratory (LBNL) and as prototype injector for the Facility for Rare Isotope Beams (FRIB) in Michigan. This work presents the latest results of an ongoing effort to simulate both, the extraction from ECR ion sources, and the Low Energy Beam Transport (LEBT). Its aim is to help understand the influence of parameters like initial ion distributions at the extraction aperture, ion temperatures and beam neutralization on the quality of the beam and to provide a design-tool for increasing the efficiency of the extraction- and transport-system. The initial conditions (i.e. spatial- and velocity-distribution of the ions prior to extraction from the ion source) are obtained semi-empirically by tracking the ions of different species from sputter marks on the biased disk on the far end of the source to the extraction region by following the magnetic field lines and scaling the Larmor radii of the ions appropriately. Extraction from the plasma and consequently the source is then simulated with the versatile WARP simulation code. The same code is also used for the actual simulation of ion transport through the beam line. Simulations of multi-species Uranium beams with different drain currents, initial ion temperatures and levels of neutralization in the beam line are compared to each other and to emittance measurements and beam profiles of VENUS beams.

Slides TUCOAK03 [2.382 MB]

TUCOAK04

Production of Highly Charged U Ion Beam from RIKEN SC-ECRIS

emittance, ECRIS, extraction, target

84

Y. Higurashi, M. Fujimaki, A. Goto, H. Haba, E. Ikezawa, O. Kamigaito, M. Kase, M. Komiyama, T. Nakagawa, J. Ohnishi, Y. Watanabe
RIKEN Nishina Center, Wako, Japan
T. Aihara, M. Tamura, A. Uchiyama
SHI Accelerator Service Ltd., Tokyo, Japan

In 2008, we successfully produced 345 MeV/u U beam (~0.4 pnA on target) for RIKEN RIBF project. However, to meet the requirement of the RIBF (primary beam intensity of 1pμA on target), we still need to increase the beam intensity. To increase the beam intensity of U ion, we started to make a test experiments for production of U ion beam from the new SC-ECRIS. In this experiment, we produced 2~1.5 pμA of medium charge state U ion (ex., 55 eμA of U³¹⁺, 57 eμA of U²⁷⁺) at the RF power of 1.2 kW with sputtering method. For testing the effect of the ionized gas on the U ion beam, we chose Ar, Ar + O₂ and O₂ gas for producing U ion beam. In this experiment, we observed that the beam intensity of lower charge state of U ion beam (<33+) was increased and the emittance of the U ion beam was decreased from ~0.1 π.mm mrad (1rms) to 0.05 π.mm mrad with adding Ar gas to O₂ gas. Using this method, we supplied U³⁵⁺ beam for ~1 month without break for the RIBF experiment. In this contribution, we present the experimental results for production of U ion beam from SC-ECRIS in detail and future plan to increase the U ion beam intensity.

Slides TUCOAK04 [1.709 MB]

TUCOBK01

Preglow Phenomenon Origins and its Scaling for Ecris

plasma, radiation, electron, ECR

87

I. Izotov, V. Sidorov, V. Skalyga, V. Zorin
IAP/RAS, Nizhny Novgorod, Russia

Preglow effect investigation is one of topical directions of ECR ion sources development at present. Preglow is of interest for efficient short-pulsed multi-charged ion source creation. Particularly, such source of intense beams of short-living radioactive isotopes multi-charged ions is one of key elements in “Beta-Beam” European project [1]. Use of Preglow-generating regime of an ECRIS operation is a promising way of pulsed high-intense multi-charged ion beams production with much shorter edges in comparison with usual operation regime. The first theoretical investigations of Preglow phenomenon were performed in references [2,3]. Present work describes modified model of ECR discharge development in a magnetic trap of the ECRIS as a continuation of [2,3]. Numerical simulations made with the updated model allow authors to propose more physical and intuitive explanation of Preglow phenomenon origins. Obtained dependences of Preglow characteristics on experimental conditions offer a scaling for a wide range of ECRISes.
[1] (ONLINE) http://beta-beam.web.cern.ch/beta-beam/task/diverse/mandate.htm
[2] T. Thuillier et al, Rev. of Sci. Instrum., 79, 02A314, 2008.
[3] I. Izotov et al, IEEE Trans. Plasma Sci. 36, 1494, 2008.

Slides TUCOBK01 [0.928 MB]

TUCOBK02

“Preglow” Investigation in ECR Discharge at 37 GHz, 100 kW

plasma, ECR, ion-source, radiation

90

V. Skalyga, I. Izotov, S. Razin, V. Sidorov, V. Zorin
IAP/RAS, Nizhny Novgorod, Russia
T. Lamy, T. Thuillier
LPSC, Grenoble, France

Multicharged ion beams generation in "Preglow" regime is now considered as the main way of short pulsed ion source creation for “Beta Beam” project. The "Preglow" effect has been investigated at a several laboratories (LPSC, JYFL, IAP RAS). The effect was discovered at LPSC on PHOENIX ion source using 18 GHz radiation for plasma heating. Investigations at 14 GHz frequency were made at JYFL. Theoretical analysis demonstrated the advantage of MW frequency increase. Theoretical calculations predict possibility of "Preglow" peaks generation with duration about tens microseconds and rather high average ion charge. At present time at LPSC a joint construction of a new generation ECR ion source with 60 GHz gyrotron plasma heating is running. As a continuation of previous research at 14, 18 and 28 GHz at present work results of experimental and theoretical "Preglow" effect investigations at SMIS 37 setup with 37,5 GHz MW plasma heating are reported. Received data are important as fundamental result in physics of ECRISs and at the same time it is the next step on the way of 60 GHz SEISM facility creation. “Preglow” effect was observed and investigated in experiments with ECR discharge stimulated with gyrotron radiation @ 37.5 GHz, 100 kW. Received dependencies of the “Preglow” parameters are in good correspondence with results of numerical simulations. It was shown in experiments that generation of “Preglow” peak with duration about 30 μs is possible.

Slides TUCOBK02 [2.338 MB]

TUCOBK03

Time Evolution of Plasma Potential in Pulsed Operation of ECRIS

plasma, electron, ion-source, ECRIS

93

O.A. Tarvainen, H. A. Koivisto, T. Ropponen, V.A. Toivanen
JYFL, Jyväskylä, Finland
Y. Higurashi, T. Nakagawa
RIKEN Nishina Center, Wako, Japan

The time evolution of plasma potential has been measured in pulsed operation mode with electron cyclotron resonance ion sources at JYFL and RIKEN. Three different ion sources with microwave frequencies ranging from 6.4 to 18 GHz were employed for the experiments. The plasma potential during the preglow and afterglow transients was compared with steady state conditions. The plasma potential was observed to increase 25-75 % during the preglow and 10-30 % during the afterglow. We describe the experimental procedure and present the results of the study in detail.

Slides TUCOBK03 [0.973 MB]

TUCOBK04

Micropulses Generation in ECR Breakdown Stimulated by Gyrotron Radiation at 37.5 GHz

plasma, ECR, electron, ion-source

96

V. Skalyga, S. Golubev, I. Izotov, S. Razin, V. Sidorov, A. Vodopyanov, V. Zorin
IAP/RAS, Nizhny Novgorod, Russia

Present work is devoted to experimental and theoretical investigation of possibility of short pulsed (< 100 μs) multicharged ion beams creation. The possibility of quasi-stationary generation of short pulsed beams under conditions of quasi-gasdynamic plasma confinement was shown in recent experiments. Later another way of such beams creation based on “Preglow” effect was proposed. In present work it was demonstrated that in the case when duration of MW pulse is less then formation time of “Preglow” peak, realization of a regime when ion current is equal to zero during MW pulse and intense multicharged ions flux appears only when MW ends could be possible. Such pulses after the end of MW were called "micropulses". In present work generation of micropulses was observed in experiments with ECR discharge stimulated by gyrotron radiation @ 37,5GHz, 100 kW. In this case pulses with duration less than 30 μs. Probably the same effect was observed in GANIL where 14 GHz radiation was used and pulses with duration about 2 ms were registered. In present work it was shown that intensity of such micropulse could be higher than intensity of “Preglow” peak at the same conditions but with longer MW pulse. The generation of micropulses of nitrogen and argon multicharged ions with current of a few mA and length about 30 μs after MW pulse with duration of 30-100 μs was demonstrated. The low level of impurities, high current density and rather high average charge make possible to consider such micropulse regime as perspective way for creation of a short pulsed ion source.

Slides TUCOBK04 [3.473 MB]

TUCOCK01

Beam, Multi-Beam and Broad Beam Production with COMIC Devices

plasma, cavity, extraction, high-voltage

99

P. Sortais, J. Angot, T. Lamy, J. Médard
LPSC, Grenoble Cedex, France
C. Peaucelle
IN2P3 IPNL, Villeurbanne, France

The COMIC discharge cavity is a very versatile technology. We will present new results and devices that match new applications like: molecular beams, ultra compact beam line for detectors calibrations, quartz source for on-line application, high voltage platform source, sputtering /assistance broad beams and finally, a quite new use, high energy multi¬-beam production for surface material modifications. In more details, we will show that the tiny discharge of COMIC can mainly produce molecular ions (H³⁺). We will present the preliminary operation of the fully quartz ISOLDE COMIC version, in collaboration with IPN-Lyon, we will present a first approach for a slit extraction version of a three cavity device, and after discussing about various extraction systems on the multi discharge device (41 cavities) we will show the low energy broad beam (2 KV) and high energy multi-beams (10 beams up to 30 KV) productions. We will specially present the different extraction systems adapted to each application and the beams characteristics which are strongly dependent on the voltage distribution of an accel-accel two electrodes extraction system.

Slides TUCOCK01 [4.960 MB]

TUCOCK02

Status of the High Current Permanent Magnet 2.45 GHz ECR Ion Source at Peking University

ion-source, plasma, ECR, extraction

102

S.X. Peng, J.E. Chen, Z.Y. Guo, P.N. Lu, Y.R. Lu, H.T. Ren, Z.Z. Song, J.X. Yu, Z.X. Yuan, M. Zhang, J. Zhao
PKU/IHIP, Beijing, People's Republic of China

Several compact 2.45 GHz Electron Cyclotron Resonance Ion Sources (ECRIS) have been developed at Peking University for ion implantation[1], separated function Radio Frequency quadruple (SFRFQ)[2] and for the Peking University Neutron Imaging Facility (PKUNIFTY)[3]. Studies are focused on methods of magnetic field generation, magnetic fields configuration, microwave window design, microwave coupling, and structure selection of extraction electrodes. Up to now, our sources have produced 25 mA O+/ He⁺ ion, 10mA N+ ion, 100 mA H⁺ and 83 mA D⁺ ions, respectively. Details will be reported in the paper.
[1] Z. Song, D. Jiang, and J. Yu, Rev. Sci. Instr., 67,1003(1996).
[2] S. X. Peng, M. Zhang, Z. Z. Song, R. Xu, J. Zhao, Z. X. Yuan, J. X. Yu, J. Chen, Z. Y. Guo, Rev. Sci. Instr., 2008, 79: 02B706.
[3] M. Zhang, S. X. Peng, H. T. Ren, Z. Z. Song, Z. X. Yuan, Q. F. Zhou, P. N. Lu, R. Xu, J. Zhao, J. X. Yu, J. E. Chen, Z. Y. Guo, and Y. R. Lu, Rev. Sci. Instr. 2010, 81:02B715.

Slides TUCOCK02 [3.144 MB]

TUCOCK03

Development of 14.5 GHz Electron Cyclotron Resonance Ion Source at KAERI

ECR, plasma, ion-source, extraction

105

B.H. Oh, D.S. Chang, C.K. Hwang, S.R. In, S.H. Jeong, J.T. Jin, K.W. Lee, C.S. Seo
KAERI, Daejon, Republic of Korea

A 14 GHz ECRIS has been designed and fabricated in KAERI (Korea Atomic Energy Research Institute) to produce multi-charged ion beam (especially for C⁶⁺ ion beam) for medical applications. The magnet system has solenoid coils made with copper conductor and a hexapole made with permanent magnet. The solenoid coils are composed of two axial coils to make mirror fields in both sides of the chamber and one trim coil at the center to control the layer of the resonance region. The hexapole is made with 24-sector NdFeB permanent magnet. Radial field higher than 1.2 T at the chamber wall position has been measured, and axial field higher than 1.7 T at the entrance center of RF power and 1.1 T at the exit center of ion beam have been measured. A welded tube with aluminum and stainless steel is used for a ECR plasma chamber to improve the production of secondary electron. Cooling channel is made on the wall of the Al tube. A 2 kW Krystron is used as a microwave energy source. A DC break made with PEEK(Polyether Ether Ketone) for high voltage insulation and field shielding, and a RF window made with ceramic for vacuum insulation are inserted in the RF circuit. A movable beam extractor with 8 mm aperture covers different species and different charge numbers of the beam. Experimental results on ECR plasma and initial beam extraction with KAERI ECR ion source will be discussed.

Slides TUCOCK03 [2.342 MB]

TUCOCK04

Mass Spectrometry with an ECR Ion Source

ion-source, background, ECR, controls

109

M.A.C. Hotchkis, D. Button
ANSTO, Menai, Australia

Several groups [1-3] have demonstrated the usefulness of ECR ion sources in forms of mass spectrometry, for the detection of rare long-lived radioisotopes, trace elements and stable isotope ratios. Mass spectrometry imposes strict constraints on the ion source. First, the ion source must be free of backgrounds at the same m/q ratio as isotope of interest. Backgrounds take several forms, including beams generated from residual gas or other materials in the source, either of the element of interest, or other elements which cause isobaric or other m/q ambiguities. Second, the ion source must exhibit a minimum ‘memory’ effect from sample to sample. We are interested in isotopic ratios of carbon, nitrogen and oxygen. These elements are ubiquitous in vacuum systems and so this work has its own particular challenges, especially in relation to the design and operational characteristics of the ion source. Initial work has revealed retention effects which reduce the sample clear out rates, and cause persistent backgrounds [4]. We will present results of our most recent efforts to control these problems.
[1] P. Collon et al., Nucl. Instrum. Methods B 2004; 223/224: 428.
[2] M. Kidera et al., Eur. J. Mass Spectrom. 2007; 13: 239.
[3] M. Hotchkis et al., Rapid Comm. Mass Spec. 2008; 22: 1408-1414.
[4] D. Button and M.A.C. Hotchkis, Proc. 18th ECRIS Workshop, Sept 15-18, 2008, Chicago, USA, http://www. JACoW.org/.

Slides TUCOCK04 [3.849 MB]

TUPOT001

Plans for Laser Ablation of Actinides into an ECRIS for Accelerator Mass Spectroscopy

laser, ECR, ion-source, ECRIS

110

R.C. Pardo, F.G. Kondev, S.A. Kondrashev, C. Nair, T. Palchan, E. Rehm, R.H. Scott, R.C. Vondrasek
ANL, Argonne, USA
P. Collon
University of Notre Dame, Notre Dame, USA
G. Imel
ISU, Pocatello, Idaho, USA
C. McGrath, G. Palmotti, M. Salvatores, G. Youinou
Idaho National Laboratory, Idaho, USA
M. Paul
The Hebrew University of Jerusalem, The Racah Institute of Physics, Jerusalem, Israel

Funding: This work is supported by the U.S. Department of Energy, Office of Nuclear Physics, under contract No. DE-AC02-06CH11357.
A project using accelerator mass spectrometry (AMS) at the ATLAS facility to measure neutron capture rates on a wide range of actinides in a reactor environment is underway. This project will require the measurement of many samples with high precision and accuracy. The AMS technique at ATLAS is based on production of highly-charged positive ions in an ECRIS followed by linear acceleration. We have chosen to use laser ablation as the best means of feeding the actinide material into the ion source because we believe this technique will have more efficiency and lower chamber contamination thus reducing ‘cross talk’ between samples. In addition a multi-sample holder/changer is part of the project to allow quick change between multiple samples. The status of the project, design, and goals for initial off-line ablation tests will be discussed as well as the overall project schedule.

Poster TUPOT001 [0.152 MB]

TUPOT002

Enhancement of ECR Performances by Means of Carbon Nanotubes Based Electron Guns

electron, plasma, gun, ECR

114

F. Odorici, M. Cuffiani, L. Malferrari, R. Rizzoli, G.P. Veronese
INFN-Bologna, Bologna, Italy
G. Castro, L. Celona, G. Ciavola, N. Gambino, S. Gammino, D. Mascali, R. Miracoli, F.P. Romano
INFN/LNS, Catania, Italy
T. Serafino
Università di Messina, Messina, Italy

One of the main goals of the scientific community which deals with ECR Ion Sources is the optimization of the Eelectron Energy Distribution Function (EEDF) inside the plasma. The EEDF consists of three different populations (cold, warm and hot electrons): the cold and the warm populations are responsible of the stabilization and of the efficient ionization of the plasma respectively. The presence of the hot population is doubly detrimental: in high frequency sources they lead to the heating of LHe in the superconducting coils’ cryostat and are also useless for the generation of high intensity ion beams, because of their small cross section. Therefore the injection of additional electrons inside the plasma may increase the density of cold and warm electrons, enabling at the same time to reduce the number of the high energy ones. The CANTES experiment tested the use of carbon nanotubes (CNTs) to emit electrons in presence of strong applied electric fields, in order to provide additional electrons to the plasma core. This technique was used with the Caesar ECR ion source, at INFN-LNS, demonstrating that the total extracted ion current is increased and that a relevant reduction of the number of “high energy” electrons (above 100 keV) can be obtained. This last result is even more important, because CNTs may be an effective and reliable tool to permit the operation of ECRIS at large power and high frequencies without any detrimental effect on the source stability and reliability coming from hot electrons. Details of the construction of CNTs based electron gun and their behaviour in plasma environments are presented. Preliminary results in terms of performances of the Caesar ECR ion source and possible future applications will be also discussed.

Poster TUPOT002 [1.914 MB]

TUPOT003

A New BETSI Test Bench at CEA/Saclay

permanent-magnet, plasma, diagnostics, solenoid

117

S. Nyckees, Y. Gauthier, C.M. Mateo
CEA/IRFU, Gif-sur-Yvette, France
G. Adroit, O. Delferrière, R.D. Duperrier, R. Gobin, F. Harrault, O. Napoly, B. Pottin, Y. Sauce, F. Senée, O. Tuske, T.V. Vacher
CEA/DSM/IRFU, France

By the 90s, CEA has undertaken to develop the production of high intensity light ion beams from plasma generated by electron cyclotron resonance (ECR). Important results were obtained with the SILHI source in pulsed or continuous mode. Presently, CEA/Saclay is now involved in the construction of different injectors dedicated to large infrastructures like IFMIF or Spiral 2. Other installations are also interested by high intensity ion sources like ESS or FAIR. To improve and test new sources, a new test bench named BETSI (Banc d'Etudes et de Tests des Sources d'Ions) is now operating for several months. Low energy beam line diagnostics consist of a Faraday cup, cameras and a species analyzer. The SILHI emittance scanner can also be installed on the beam line. On this test bench, different permanent magnet source configurations are tested. In order to modify plasma chamber size and shape, a new ECR source design is developed. An experimental study of the plasma visible light emitted through electrodes was implemented on BETSI using a monochromator. Extracted beam intensity of a permanent magnet source is compared to plasma light emission. Results obtained with monochromator will be compared with SOLMAXP code in order to explore radio frequency wave and plasma interaction.

Poster TUPOT003 [4.044 MB]

TUPOT004

Microgan ECR Ion Source in a Van de Graaff Accelerator Terminal

ion-source, controls, high-voltage, ECR

120

G. Gaubert, C. Bieth, W. Bougy, B.N. Brionne, X. Donzel, A. Sineau, O. Tasset, C. Vallerand, A.C.C. Villari
PANTECHNIK, BAYEUX, France
C. Chavez-de-Jesus, T. Gamboni, W. Geerts, G. Giorginis, R. Jaime Tornin, G. Lövestam, W. Mondelaers
JRC/IRMM, Geel, Belgium

The Van de Graaff accelerator at IRMM works since many years providing proton, deuteron and helium beams for nuclear data measurements. The original ion source was of RF type with quartz bottle. This kind of source, as well known, needs regular maintenance for which the accelerator tank must be completely opened. The heavy usage at high currents of the IRMM accelerator necessitated an opening about once every month. Recently, the full permanent magnet Microgan ECR ion source from PANTECHNIK was installed into a new terminal platform together with a solid state amplifier of 50W, a dedicated dosing system for 4 gases (with respective gas bottles H2, D2, He and Ar), and a set of dedicated power supplies and electronic devices for the remote tuning of the source. The new system shows a very stable behavior of the produced beam allowing running the Van de Graff without maintenance for several months. This contribution will describe the full installed system in details (working at high pressure in the terminal, spark effects and optic of the extraction).

Poster TUPOT004 [1.715 MB]

TUPOT005

An ECR Table Plasma Generator

plasma, ECR, ECRIS, vacuum

124

R. Rácz, S. Biri
ATOMKI, Debrecen, Hungary
J. Pálinkás
DU, Debrecen, Hungary

A simple ECR plasma device was built in our lab using the “spare parts” of the ATOMKI ECR ion source. We call it “ECR table plasma generator”. It consists of a relatively big plasma chamber (ID=10 cm, L=40 cm) in a thin NdFeB hexapole magnet with independent vacuum and gas dosing systems. For microwave coupling two low power TWTAs can be applied individually or simultaneously, operating in the 6-18 GHz range. There is no axial magnetic field and there is no extraction. The intended fields of usage of the plasma generator are:

A simple, cheap and safe educational working place for students.
To prepare, to test or to simulate measurements with electrostatic movable Langmuir probes. The exchange time of the (damaged) probes is very short.
To prepare, to test or to simulate plasma diagnostic measurements in the visible light and X-ray ranges using cameras and spectrometers.
To cover and/or to modify solid surfaces with plasma particles, including fullerenes.

In the paper the technical details of the plasma generator and some preliminary plasma photo results are shown.

Poster TUPOT005 [0.871 MB]

TUPOT006

Using Mass-Flow Controllers for Obtaining Extremely Stable ECR Ion Source Beams

injection, ECR, controls, ion-source

127

X. Donzel, W. Bougy, B.N. Brionne, G. Gaubert, A. Sineau, O. Tasset, C. Vallerand, A.C.C. Villari
PANTECHNIK, BAYEUX, France
R. Leroy
GANIL, Caen, France

Beam stability and reproducibility is of paramount importance in applications requiring precise control of implanted radiation dose, like in the case of Hadrontherapy. The beam intensity over several weeks or months should be kept constant. Moreover, the timing for changing the nature of the beam and, as a consequence, the tuning of the source should be minimized. Standard valves usually used in conjunction of ECR ion sources have the disadvantage of controlling the conductance, which can vary significantly with external conditions, like ambient temperature and inlet pressure of the gas. The use of flow controllers is the natural way for avoiding these external constraints. In this contribution we present the results obtained using a new model of Mass-flow controller in the source Supernanogan, for production of C⁴⁺ and H³⁺ beams. Extremely stable beams (± 2.5%) without retuning of the source over several weeks could be obtained. The reproducibility of the source tuning parameters could also be demonstrated.

Poster TUPOT006 [4.386 MB]

TUPOT007

Preliminary Design of BLISI, an Off Resonance Microwave Proton Source

plasma, extraction, proton, resonance

130

S. Djekic, I. Bustinduy, D. Cortazar, D. Fernandez-Cañoto, H. Hassanzadegan, J.L. Munoz, D. de Cos
ESS Bilbao, Bilbao, Spain
F.J. Bermejo
Bilbao, Faculty of Science and Technology, Bilbao, Spain
M.A. Carrera, J.H. Galipienzo
AVS, Eibar, Gipuzkoa, Spain
V. Etxebarria, J. Jugo, J. Portilla
University of the Basque Country, Faculty of Science and Technology, Bilbao, Spain
J. Feuchtwanger, I. Rueda
ESS-Bilbao, Zamudio, Spain
J. Lucas
Elytt Energy, Madrid, Spain

A new high current off resonance microwave H⁺ source is currently in the last stages of design at ESS-Bilbao, in collaboration with two external companies Elytt and AVS. The design is intended to be a high-stability, high-current ion source capable of delivering a 70 mA proton beam with a 70 keV energy at the end of the extraction. The plasma system designed by Elytt consists of a water-cooled plasma chamber that sits between two independently powered magnetic coils that generate the ECR magnetic field; in addition they can be moved independently to further shape the magnetic field in the chamber. A CPI 2.7 GHz klystron provides the microwave energy and a fully controlled microwave system to minimize reflected power and improve the source overall performance is also under construction. The extraction column designed by AVS will consist of a movable tetrode system designed for a maximum acceleration potential of 70 kV, the shape of the electrodes is at an earlier design stage at ESS-Bilbao. We will present the current layout of the source, simulations and schematics of the source.

Poster TUPOT007 [3.954 MB]

TUPOT008

Performance of the LBNL AECR-U with a TWTA

plasma, resonance, coupling, ion-source

133

J.Y. Benitez, D. Leitner, C.M. Lyneis
LBNL, Berkeley, California, USA
M.K. Covo
LLNL, Livermore, California, USA

The Advanced Electron Cyclotron Resonance - Upgrade ion source (AECR-U) at the Lawrence Berkeley National Laboratory has successfully utilized double frequency microwave heating (14.3 GHz and 10.4 GHz) for several years [1]. Recently a traveling wave tube amplifier (TWTA), providing frequencies in the range of 10.75GHz-12.75GHz, was added as a secondary heating frequency, replacing the previous 10.4 GHz Klystron. The TWTA opens the possibility to explore a wide range of secondary frequencies and a study has been conducted to understand and optimize its coupling into the AECR-U. In particular, the reflected power dependence on heating frequency has been mapped out with and without the presence of plasma. A comparison is made to determine how the presence of plasma, confinement fields, and other source parameters affect the reflected power and if and how the amount of reflected power can be correlated to the source ion beam performance.
[1] Z. Q. Xie and C. M. Lyneis, Rev. Sci. Instrum. 66 (1995).

Poster TUPOT008 [0.213 MB]

TUPOT009

Measurements of Bremsstrahlung Radiation and X-Ray Heat Load to Cryostat on SECRAL

radiation, electron, ECR, plasma

134

H. Zhao, Y. Cao, X.X. Li, D. Xie, W.H. Zhang, X.Z. Zhang, H.W. Zhao, Y.H. Zhu
IMP, Lanzhou, People's Republic of China
W. Lu
Graduate School of the Chinese Academy of Sciences, Beijing, People's Republic of China

Measurement of Bremsstrahlung radiation from ECR plasma can yield certain information of the ECR heating process and a plausible estimate of the X-ray heat load to the cryostat of a superconducting ECR source which needs seriously addressed. With a newly-developed collimation system, which defines a narrower spatial range of the measurement and provides an effective shielding from the background, a systematic measurement of the Bremmstrahlung emitted axially from the SECRAL (Superconducting ECR Ion Source with Advanced design in Lanzhou) plasma were carried out recently. The spectral temperature Tspe, a relative index of mean energy of the plasma hot electrons, was derived through linear fitting of the spectra in semi-logarithm coordinates. This article will present and discuss the evolutions of the X-ray flux and the hot electron energy with various source parameters, such as heating frequency, RF power and magnetic field configuration. And possible solutions to reduce the X-ray heat load induced by Bremsstrahlung radiation are proposed and discussed.

Poster TUPOT009 [1.581 MB]

TUPOT010

Effects of Microwave Frequency Fine Tuning on the Performance of JYFL 14 GHz ECRIS

plasma, ion-source, emittance, ECRIS

137

V.A. Toivanen, V.P. Aho, J. Ärje, P. Jones, J.A. Kauppinen, H. A. Koivisto, P. Peura, O.A. Tarvainen
JYFL, Jyväskylä, Finland
L. Celona, G. Ciavola, S. Gammino
INFN/LNS, Catania, Italy
A. Galatà
INFN/LNL, Legnaro (PD), Italy
D. Mascali
CSFNSM, Catania, Italy
T. Ropponen
NSCL, East Lansing, Michigan, USA

Measurements have been carried out at Department of Physics, University of Jyväskylä (JYFL) to study the effects of microwave frequency fine tuning on the performance of JYFL 14 GHz electron cyclotron resonance ion source. The frequency was varied within an 85 MHz band around the normal operation frequency of 14.085 GHz. The radial bremsstrahlung emission was measured for plasma diagnostics purposes and mass separated ion beam currents extracted from the ion source were recorded at the same time. Also, beam quality studies were conducted by measuring the ion beam emittance and shape with and without enhanced space charge compensation. The obtained results are presented and possible origins of seen phenomena in measured quantities are discussed.

Poster TUPOT010 [0.678 MB]

TUPOT012

Microwave Frequency Dependence of the Properties of the Ion Beam Extracted From a Caprice Type ECRIS

plasma, ECRIS, ECR, ion-source

143

F. Maimone, R. Lang, J. Mäder, J. Roßbach, P. Spädtke, K. Tinschert
GSI, Darmstadt, Germany
L. Celona
INFN/LNS, Catania, Italy
F. Maimone
DMFCI, Catania, Italy

In order to improve the quality of ion beams extracted from ECR ion sources it is mandatory to better understand the relations between the plasma conditions and the beam properties. The present investigations concentrate on the analysis of different beam properties under the influence of various applications of frequency tuning and of multiple frequency heating. The microwave frequency feeding the plasma affects the electromagnetic field distribution and the dimension and position of the ECR surface inside the plasma chamber. This in turn has an influence on the generation of the extracted ion beam in terms of its intensity, of its shape and of its emittance. In order to analyze the corresponding effects measurements have been performed with the Caprice type ECRIS installed at the ECR Injector Setup (EIS) of GSI. The experimental setup uses a new arrangement of one or more microwave sweep generators which feed a Traveling Wave Tube amplifier covering a wide frequency range from 12.5 to 18 GHz. This arrangement provides a precise determination of the frequencies and of the reflection coefficient along with the beam properties. A sequence of viewing targets positioned inside the beam line monitors the beam shape.

Poster TUPOT012 [1.245 MB]

TUPOT013

Influence of Initial Plasma Density and Mean Electron Energy on the Preglow Effect

plasma, simulation, electron, ECR

146

I. Izotov, V. Sidorov, V. Skalyga, V. Zorin
IAP/RAS, Nizhny Novgorod, Russia
H. A. Koivisto, O.A. Tarvainen, V.A. Toivanen
JYFL, Jyväskylä, Finland

The investigation of the Preglow effect is driven with the aim of creating a short-pulsed multicharged ion source. Recent experimental investigations have revealed strong influence of seed electrons, i.e. initial plasma density, on the amplitude and duration of the Preglow peak [1]. Present work, consisting of experiments and simulations, is dedicated to further investigation of the Preglow dependence on initial plasma density and electrons energy. Experimental investigation was performed at University of Jyväskylä (JYFL) with the A-ECR type ECRIS operated with 14 GHz frequency. Helium was used for the study. An initial ionization degree of the gas was varied by changing the pulse duration and duty factor. Time-resolved ion currents of He⁺ and He²⁺ were recorded. Calculations were made by using 0-dimensional model described in references [2], [3] and based on the balance equations for the particles confined in the magnetic trap. Results of simulation are compared with experimental Preglow peaks and discussed. Good agreement between experimental data and simulation encourages us to conduct a further study, aimed at optimizing the Preglow by tuning source parameters and initial plasma conditions.
[1] O. Tarvainen et al, Rev. Sci. Instrum., 81, 02A303, 2010.
[2] T. Thuillier et al, Rev. Sci. Instrum., 79, 02A314, 2008.
[3] I. Izotov et all. IEEE Trans. Plasma Sci. 36, 1494, 2008.

Poster TUPOT013 [0.569 MB]

TUPOT014

Optimized Extraction Conditions From High Power ECRIS by Dedicated Dielectric Structures

plasma, extraction, electron, ECRIS

147

L. Schächter, S. Dobrescu
IFIN, Magurele- Bucuresti, Romania
K.E. Stiebing
IKF, Frankfurt-am-Main, Germany

The MD-method of enhancing the ion output from ECR ion sources is well established and basically works via two mechanisms, the regenerative injection of cold electrons from an emissive dielectric layer on the plasma chamber walls and via the cutting of compensating wall currents, which results in an improved ion extraction from the plasma. As this extraction from the plasma becomes a more and more challenging issue for modern ECRIS installations with high microwave power input, a series of experiments was carried out at the 14 GHz ECRIS of the Institut für Kernphysik in Frankfurt/Main, Germany (IKF). In contrast to our earlier work, in these experiments emphasis was put on the second of the above mechanisms namely to influence the sheath potential at the extraction by structures with special dielectric properties. Two different types of dielectric structures, Tantalum-oxide and Aluminum oxide (the latter also being used for the MD-method) with contrastingly different electrical properties were mounted on the extraction electrode of the IKF-ECRIS, facing the plasma. For both structures an increase of the extracted ion beam currents for middle and high charge states by 60-80 % was observed. The method is able to be applied also to other ECR ion sources for increasing the extracted ion beam performances.

Poster TUPOT014 [0.510 MB]

TUPOT015

Permanent Magnet ECRIS for the KEK Digital Accelerator

ECRIS, plasma, high-voltage, ion-source

150

K.W. Leo, T. Adachi
Sokendai, Ibaraki, Japan
T. Arai, K. Koyama, M. Wake
KEK, Ibaraki, Japan
K. Okazaki
Nippon Advanced Technology Co. Ltd., Ibaraki-prefecture, Japan
K. Takayama
TIT, Yokohama, Japan

The existing KEK 500 MeV booster synchrotron is renovated into a digital accelerator (DA) capable of accelerating all species of ion [1]. The KEK-DA is an induction synchrotron employing no large injector. Its concept was demonstrated in 2006 using the 12 GeV proton synchrotron [2,3], where a proton bunch was accelerated with pulse voltages generated by a transformer instead of RF. In the KEK-DA, O, Ne, and Ar ions from the ECRIS embedded in the 200 kV high-voltage terminal (HVT) are directly injected into the ring though the low energy beam transport line. The permanent magnet ECRIS, in which a plasma is fired by x-band microwave pulses of 3 msec at 10 Hz, has been assembled at KEK. Its operational performance such as charge-state spectrum, emittance, and current is tested since the last year. In addition, the HVT with a voltage stabilizing circuit is being assembled now. Beam dynamical analysis from the cathode hall to the separation magnet, where possible charge-state ions are contaminated in the space-charge limit and beam focusing is realized through the Einzel lens and tandem acceleration gaps, is discussed as well as operational characteristics of the ECRIS.
[1] K. Takayama et al., “All-ion Accelerator: an Injector-free Synchrotron”, J. of Appl. Phys. 101, 063304(2007).
[2] K. Takayama et al., “Experimental Demonstration of the Induction Synchrotron”, Phys. Rev. Lett. 98, 054801 (2007).
[3] K. Takayama and R.Briggs (Eds.), Induction Accelerators (Springer-Verlarg, 2010).

Poster TUPOT015 [1.947 MB]

TUPOT016

Long-Term Operation Experience With Two ECR Ion Sources and Planned Extensions at HIT

ion-source, extraction, proton, linac

153

T. Winkelmann, R. Cee, Th. Haberer, B. Naas, A. Peters
HIT, Heidelberg, Germany

The HIT (Heidelberg Ion Beam Therapy Center) is the first hospital-based treatment facility at a hospital in Europe where patients can be treated with protons and carbon ions. Since the commissioning starting in 2006 two 14.5 GHz electron cyclotron resonance ion sources are routinely used to produce a variety of ion beams from protons up to oxygen. The operating time is 330 days per year, our experience after three years of continuous operation will be presented. In the future a helium beam for patient treatment is requested, therefore a third ion source will be integrated. This third ECR source with a newly designed extraction system and a spectrometer line will be installed at a testbench to commission and validate this section. Different test settings are foreseen to study helium operation as well as enhanced parameter sets for proton and carbon beams in combination with a modified beam transport line for higher transmission efficiency. An outlook to the possible integration scheme of the new ion source into the production facility will be discussed.

Poster TUPOT016 [4.294 MB]

TUPOT017

CEA/Saclay Light Ion Sources Status and Developments

plasma, ion-source, extraction, emittance

156

R. Gobin, C.M. Mateo, S. Nyckees
CEA/IRFU, Gif-sur-Yvette, France
G. Adroit, G. Bourdelle, N. Chauvin, O. Delferrière, Y. Gauthier, P. Girardot, F. Harrault, C. Marolles, B. Pottin, Y. Sauce, F. Senée, O. Tuske, T.V. Vacher, C. Van Hille
CEA/DSM/IRFU, France

After several years of high intensity light ion beam production with the SILHI source, CEA Saclay is now involved in the construction of different injectors dedicated to large infrastructures like IFMIF or Spiral 2. Other installations are also interested by high intensity ion sources like ESS or FAIR. Such machines plan to produce and accelerate proton or deuteron beams in pulsed or continuous mode. The SILHI source, based on ECR plasma generation, already demonstrated its performance in both modes. As a consequence, at present time the construction of 2 new injectors for Spiral 2 and IFMIF (source and low energy beam lines) is in progress at CEA/Saclay. This article will report on the status of both installations. It will also point out on additional developments presently under progress for high intensity beam characterization or plasma production understanding. Such developments are mainly done with the new BETSI test bench operating for several months.

Poster TUPOT017 [2.020 MB]

TUPOT018

Sheath Formation of a Plasma Containing Multiply Charged Ions, Cold and Hot Electrons, and Emitted Electrons

electron, plasma, resonance, ion-source

159

H.J. You
NFRI, Daejon, Republic of Korea

A model of sheath formation was extended to a plasma containing multiply charged ions (MCIs), cold and hot electrons, and secondary electrons emitted either by MCIs or hot electrons. The present study was motivated by the fact that the secondary electron yields are strongly dependent on the charge state of the ions and on the incident energy of electrons. Therefore, the contributions of the secondary electron emissions on the sheath formation would be severe in ECRIS plasmas where the charge state of ions is high and highly energetic electrons exist. In the model, modification of the “Bohm criterion” was given; thereby the sheath potential drop and the critical emission condition were analyzed. The model calculations were made mainly on the effects of the emitted electrons on the variations of the sheath potential drop, the particle and heat flux to the wall, by which some explanations for the effect of secondary electrons in ECR ion sources are given.

Poster TUPOT018 [0.259 MB]

WECOAK01

Characterization of the Microwave Coupling to the Plasma Chamber of the LBL ECR Ion Source.

plasma, cavity, coupling, ECR

162

C.M. Lyneis, J.Y. Benitez, D. Leitner, J.D. Noland, M.M. Strohmeier
LBNL, Berkeley, California, USA
H. A. Koivisto, O.A. Tarvainen
JYFL, Jyväskylä, Finland

The characteristics of the microwave coupling of the 6.4 GHz ECR ion source were measured as a function of frequency, input power and time dependence. In addition the plasma diamagnetism and bremsstrahlung could be measured to help quantify the time dependence of the plasma build up and energy content. The LBL ECR plasma chamber, which has a diameter to wavelength ratio of 1.9 is not as over-moded as the 14 GHz AECR-U, which has a ratio greater than 3. This makes it possible to locate frequencies, where a single RF mode is predominately excited. For one of these modes we were able to demonstrate that with no plasma in the cavity, it is over-coupled and as the power is increased, the plasma density rises and the plasma loading increases it becomes under-coupled. By measuring the ratio of the incident to reflected power it is possible to show the microwave electric field levels saturate with increasing power. In the paper, the time dependence of the plasma loading and plasma diamagnetism as a function of input power and time are analyzed. The measurements of the plasma loading also provide insight into the dynamics of microwave heating in a multimode cavity.

Slides WECOAK01 [1.593 MB]

WECOAK02

Some Considerations About Frequency Tuning Effect in ECRIS Plasmas

plasma, electron, simulation, resonance

165

D. Mascali, G. Castro, L. Celona, G. Ciavola, N. Gambino, S. Gammino, R. Miracoli, L. Neri
INFN/LNS, Catania, Italy
F. Maimone
GSI, Darmstadt, Germany

During the last years many experiments have demonstrated that slight variations in microwave frequency used to heat and sustain the plasma of ECRIS may strongly influence their performances (frequency tuning effect) both in terms of extracted current and mean charge state. Theoretical investigations revealed that this phenomenon can be correctly explained assuming that the plasma chamber works as a resonant cavity: standing waves are excited inside of it, and their spatial structure considerably changes even with slight variations of the pumping frequency. Therefore some particular modes present a higher electric field on the resonance surface, that is the only region in which the energy transfer from waves to electrons occurs. Experimental measurements carried out on microwave discharge plasmas at high density (up to 10¹¹ cm^-3) featured that even if the absorption of electromagnetic energy at the ECR surface is evident, the stochastic nature of the wave-electron interaction allows the wave to be reflected at the extraction flange, thus forming a standing wave. The model here proposed, and based on PIC and MonteCarlo collisional simulations, puts in evidence that the frequency tuning effect in ECRIS has a global influence on plasma properties: it strongly affects both ion and electron dynamics. Electron heating, electron density distribution, ion formation and acceleration at resonance surface, beam formation are determined by the particular mode excited inside the cavity. This means that the frequency tuning will be an important tool for future ECRIS for the optimization of the beam quality (emittance, etc.).

Slides WECOAK02 [4.765 MB]

WECOAK03

Studies of the ECR Plasma in the Visible Light Range

plasma, ECR, ECRIS, electron

168

S. Biri, R. Rácz
ATOMKI, Debrecen, Hungary
J. Pálinkás
DU, Debrecen, Hungary

In order to investigate experimentally ECR plasmas one way is to record their optical spectra or photos in the infra-red, visible light (VL), ultra-violet or X-ray regions. The measurements and analysis of photos and spectra taken in any of these regions are usually affordable tasks. The non-destroying nature of this method is certainly an advantage, but the drawback is that the recorded information in most cases means integration over a specific line-of-sight in the plasma volume. Recently high resolution VL plasma photographs were taken at the ATOMKI-ECRIS using an 8 megapixel digital camera. Plasmas were generated from eight gases (He, methane, N, O, Ne, Ar, Kr, Xe) and from their mixtures. The analysis of the photo series gave us many qualitative and numerous valuable physical information on the nature of ECR plasmas [1, 2]. It is a further challenging task to understand the colors of this special type of plasmas. The colors can be determined by the VL electron transitions of the plasma atoms and ions. Through the examples of He and Xe we analyze the physical processes which effects the characteristic colors of these plasmas.
[1] Rácz R., Biri S., Pálinkás J.: Electron cyclotron resonance plasma photos. Rev. Sci. Instrum. 81 (2010) 02B708.
[2] Rácz R., Biri S., Pálinkás J.: ECR Plasma Photographs as Plasma Diagnostic. Submitted to Plasma Sources Science and Technology.

Slides WECOAK03 [1.573 MB]

WECOAK04

Bremsstrahlung and Ion Beam Current Measurements With SuSI ECR Ion Source

plasma, radiation, collimation, extraction

171

T. Ropponen, D.G. Cole, G. Machicoane, A. Stolz, L.T. Sun, L. Tobos
NSCL, East Lansing, Michigan, USA

The Superconducting Source for Ions (SuSI) at the National Superconducting Cyclotron Laboratory at Michigan State University is a fully superconducting 3rd generation ECR ion source. The axial magnetic field is generated by six solenoid magnets which allow to control the magnetic field characteristics, such as resonance locations, mirror ratios and magnetic field gradients, almost independently. In addition, a collimation scheme in the SuSI beam line after the analyzing magnet has been developed to optimize the ion beam production from the ion source within a given acceptance. These aspects make SuSI an excellent tool for ECRIS research and development. In this paper we will focus on the bremsstrahlung and ion beam current measurements where the gradient on the magnetic field is changed while keeping the Bmin and axial plasma length as constants. We will also show how the shift of the extraction side resonance location affects the extracted ion beam currents and radiation spectra and, finally, we will discuss about the effect of flatB mode with a modern superconducting ECR ion source on the ion beam production and radiation levels.

Slides WECOAK04 [3.752 MB]

WECOBK01

Commissioning of the ECRIS Charge State Breeder at TRIUMF

ion-source, target, TRIUMF, background

178

F. Ames, R.A. Baartman, P.G. Bricault, K. Jayamanna
TRIUMF, Canada's National Laboratory for Particle and Nuclear Physics, Vancouver, Canada
T. Lamy
LPSC, Grenoble, France

Radioactive isotopes produced at the ISOL facility ISAC at TRIUMF are usually extracted from the target ion source system as singly charged ions. If the mass of those ions exceeds A=30 their acceleration requires the breeding to highly charged ions. A modified version of an ECRIS charge breeder (14.5 GHz PHOENIX from Pantechnik) has been installed and a first on-line test resulting in the successful acceleration of ⁸⁰Rb¹⁴⁺ has been performed already in 2008. During the radioactive beam time periods of 2009 and 2010 further measurements with stable and radioactive ions from different target ion source combinations have been performed to fully commission the system. Breeding efficiencies of several percent in the maximum of the charge state distribution have been achieved. Detailed results will be presented.

Slides WECOBK01 [1.230 MB]

WECOBK02

Recent Performance of the ANL ECR Charge Breeder

injection, plasma, ECR, extraction

181

R.C. Vondrasek, A. Kolomiets, R.C. Pardo, R.H. Scott
ANL, Argonne, USA

Funding: This work was supported by the U.S. Department of Energy, Office of Nuclear Physics, under Contract No. DE-AC02-06CH11357.
The construction of the Californium Rare Ion Breeder Upgrade (CARIBU), a new radioactive beam facility for the Argonne Tandem Linac Accelerator System (ATLAS), is nearing completion. The facility will use fission fragments, with charge 1+ or 2+, from a 1 Ci ²⁵²Cf source; thermalized and collected into a low-energy particle beam by a helium gas catcher. An existing ATLAS ECR ion source was modified to function as a charge breeder in order to raise the ion charge sufficiently for acceleration in the ATLAS linac. A surface ionization source or an RF discharge source provide beams for charge breeding studies. An achieved efficiency of 11.9% for ⁸⁵Rb¹⁹⁺, with a breeding time of 200 msec, and 15.6% for ⁸⁴Kr¹⁷⁺ has been realized. Both results are with the source operating with two RF frequencies (10.44 + 11.90 GHz). After modification to the injection side iron plug, the charge breeder has been operated at 50 kV, a necessary condition for the resolution of the isobar separator.

Slides WECOBK02 [3.351 MB]

WECOBK03

Fine Frequency Tuning of the PHOENIX Charge Breeder Used as a Probe for ECRIS Plasmas

plasma, injection, ECR, ion-source

184

T. Lamy, J. Angot, M. Marie-Jeanne, J. Médard, P. Sortais, T. Thuillier
LPSC, Grenoble Cedex, France
A. Galatà
INFN/LNL, Legnaro (PD), Italy
H. A. Koivisto, O.A. Tarvainen
JYFL, Jyväskylä, Finland

Fine frequency tuning of ECR ion sources is a main issue to optimize the production of multiply charged ion beams. The PHOENIX charge breeder operation has been tested in the range 13,75 - 14,5 GHz with an HF power of about 400 W. The effect of this tuning is analyzed by measuring the multi-ionization efficiency obtained for various characterized injected 1+ ion beams (produced by the 2.45 GHz COMIC source). The 1+/n+ method includes the capture and the multi ionization processes of the 1+ beam and may be considered as a plasma probe. The n+ spectra obtained could be considered, in first approach, as an image of the plasma of the charge breeder. However, in certain conditions it has been observed that the injection of a few hundreds of nA of 1+ ions (i.e.: Xe¹⁺) in the plasma of the charge breeder, is able to destroy the charge state distribution of the support gas (i.e.: up to 40 % of O⁶⁺ and O⁷⁺ disappears). The study of this phenomenon will be presented along with plasma potential measurements for various charge states. This study may help to understand the ECRIS creation (or destruction) of highly charged ions.

Slides WECOBK03 [7.745 MB]

WECOBK04

Preliminary Results of Spatially Resolved ECR Ion Beam Profile Investigations

extraction, ion-source, ECR, ECRIS

188

L. Panitzsch, M. Stalder, R.F. Wimmer-Schweingruber
IEAP, Kiel, Germany

The Department of Experimental and Applied Physics (IEAP) at the University of Kiel (CAU Kiel) is establishing a solar wind laboratory for the calibration of space instrumentation. The main item of this facility is a 11GHz (Plateau) ECR ion source. It can be operated at two different radial magnetic confinements, using a set of permanent magnets in either hexapole or dodekapole arrangement. While beam focussing by moving the extraction along the beam line to match the ion beam into the analysing magnet is well known, little is known about beam steering by moving the extraction in the plane perpendicular to the beam line. For the hexapole-configuration we will present our results about the feasibility of ion beam focussing and steering using a 3D-movable extraction. The beam profiles of these measurements will be recorded in comparatively high resolution with a Faraday cup array (see paper doi: 10.|10|63/1.3246787). This method will be shortly introduced within this talk, as well.

Slides WECOBK04 [13.317 MB]

THCOAK01

A Correction Scheme for the Hexapolar Error of an Ion Beam Extracted from an ECRIS

simulation, plasma, extraction, emittance

191

P. Spädtke, R. Lang, J. Mäder, F. Maimone, J. Roßbach, K. Tinschert
GSI, Darmstadt, Germany

The extraction of any ion beam from ECRIS is determined by the good confinement of such ion sources. It has been shown earlier, that the ions are coming from these places, where the confinement is weakest. The assumption that the low energy ions are strongly bound to the magnetic field lines require furthermore, that only these ions which start on a magnetic field line which go through the extraction aperture can be extracted. Depending on the setting of the magnetic field, these field lines may come from the loss lines at plasma chamber radius. Because the longitudinal position of these field lines depends on the azimuthal position at the extraction electrode, the ions are extracted from different magnetic flux densities. Whereas the solenoidal component is not curable, the hexapolar component can be compensated by an additional hexapole after the first beam line focusing solenoid. The hexapole has to be rotatable in azimuthal direction and moveable in longitudinal direction. For a good correction the beam needs to have such a radial phase space distribution, that the force given by this hexapole act on the aberrated beam exactly in such a way to create a linear distribution after that corrector.

Slides THCOAK01 [1.115 MB]

THCOAK02

Kinetic Plasma Simulation of Ion Beam Extraction from an ECR Ion Source

simulation, ECR, electron, ion-source

194

S.M. Elliott, E.K. White
Thin Film Consulting, Longmont, Colorado, USA
J. Simkin
Vector Fields Ltd., Oxford, United Kingdom

Designing optimized ECR ion beam sources can be streamlined by the accurate simulation of beam optical properties in order to predict ion extraction behavior. The complexity of these models, however, can make PIC-based simulations time-consuming. In this paper, we first describe a simple kinetic plasma finite element simulation of extraction of a proton beam from a permanent magnet hexapole electron cyclotron resonance (ECR) ion source. Second, we analyze the influence of secondary electrons generated by ion collisions in the residual gas on the space charge of a proton beam of a dual-solenoid ECR ion source. The finite element method (FEM) offers a fast modeling environment, allowing analysis of ion beam behavior under conditions of varying current density, electrode potential, and gas pressure.

Slides THCOAK02 [0.821 MB]

THCOAK03

Dipole Magnet Optimization for High Efficiency Low Energy Beam Transport

emittance, simulation, ECRIS, extraction

197

S. Saminathan, J.P.M. Beijers, S. Brandenburg, V. Mironov, J. Mulder
KVI, Groningen, The Netherlands

Losses in the low-energy beam transport line from KVI-AECRIS to AGOR cyclotron are estimated to be around 50%. Numerical simulations of the beam transport were performed using the tracing code LORENTZ-3D. It was found that most of the losses are due to second order optical aberrations in the 110-degree analyzing magnet. These aberrations result in an increase of the effective emittance in both horizontal and vertical directions. We will show that by suitably modifying the magnet pole surfaces the second-order aberrations can be compensated to a large extent resulting in a substantially lower effective emittance of the transported beam.

Slides THCOAK03 [1.102 MB]

THCOAK04

Modeling ECRIS Using a 1D Multifluid Code

extraction, ECR, ion-source, instrumentation

200

M. Stalder
IEAP, Kiel, Germany

We developed a one-dimensional (1D) multifluid code to simulate the production and the transport of multiple ion species in an electron cyclotron ion source (ECRIS). The ion species are assumed to be highly collisionally coupled. Each ion species is treated as a independent fluid. This allows us to study the influence of the ion temperature. The temperature is assumed to be equal for all charge states and in the whole ECRIS. As starting parameters we choose a hot magnetically trapped electron distribution, a cold electron distribution trapped by the plasma potential an the neutral density. Modeling the interaction of the different fluids led to a new understanding of the influence of the electrostatic potential that balances the pressure gradient of the ions species in the ECRIS. The highest charge states are not confined strongest as in the over barrier model but expelled in comparison to lower charge states. It can be shown that the relative velocity v of the treated fluids scales as v ~ T^5/3 with the ion temperature. First results of the simulations are presented together with a discussion of the modeling approach for the multifluid case and its theoretical predictions. As a baseline for our simulations we mainly used the results of the 1D GEM ECRIS fluid simulations.

Slides THCOAK04 [2.268 MB]

THCOBK01

Concluding Remarks

ion-source, ECR, plasma, ECRIS

201

T. Nakagawa
RIKEN Nishina Center, Wako, Japan

Concluding remarks kindly done by Takahide Nakagawa

Slides THCOBK01 [0.436 MB]