ECRIS2010 - List of Keywords (ECRIS)

Paper	Title	Other Keywords	Page
MOCOAK02	Intense Beam Production with SuSI	ion, ECR, ion-source, 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	ion, ECR, ion-source, 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]

MOCOCK03	Design Study of a Higher Magnetic Field SC ECRIS at IMP	plasma, solenoid, sextupole, ion	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	ion, 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]

MOPOT002	Two-Chamber Configuration of the Bio-Nano ECRIS	ion, plasma, 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]

MOPOT010	The Light Ion Guide CB-ECRIS Project at the Texas A&M University Cyclotron Institute	ion, 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]

MOPOT011	DRAGON: a New 18 GHz RT ECR Ion Source with a Large Plasma Chamber	plasma, sextupole, extraction, injection	58
	W. Lu, D. Xie, X.Z. Zhang, H.W. Zhao IMP, Lanzhou, People's Republic of China W. Lu Graduate School of the Chinese Academy of Sciences, Beijing, People's Republic of China L. Ruan, F.C. Song, B. Xiong, S. Yu, J. Yuan IEE, Beijing, People's Republic of China
	Building a strong radial magnetic field with a permanent hexapole magnet for an ECRIS is extremely challenging so that the conventional wisdom requires a small but not optimal plasma chamber that is typically of ID less or equal to 80 mm. A new 18 GHz RT ECR ion source, DRAGON, has been designed with a large bore permanent hexapole and source construction has begun at IMP. Its plasma chamber is of ID of 126 mm, the same as that of the superconducting ion source SECRAL, with maximum radial field strength reaching 1.5 Tesla at the plasma chamber wall. The overall magnetic strengths of DRAGON, with maximum axial fields of 2.7 Tesla at the injection and 1.3 Tesla at the extraction, are very similar to those of SECRAL operating at 18 GHz and hopefully the SECRAL performance. The source solenoid magnet coils are cooled by an evaporative coolant at about 50 degree C. In addition, the source is thickly insulated for beam extraction at 50 kV and higher voltage up to 100 kV can be explored. This article will present the design details and discussions of this new ion source.
	Poster MOPOT011 [0.563 MB]

MOPOT013	MONOBOB II : Latest Results of Monocharged Ion Source for SPIRAL2 Project	target, ion, 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	ion, 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, ion-source, ion, 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]

MOPOT017	Tests of a New Axial Sputtering Technique in an ECRIS	plasma, ECR, ion, 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, ion-source, 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	ion, emittance, simulation, beam-transport	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]

TUCOAK04	Production of Highly Charged U Ion Beam from RIKEN SC-ECRIS	ion, emittance, 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]

TUCOBK03	Time Evolution of Plasma Potential in Pulsed Operation of ECRIS	plasma, ion, electron, ion-source	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]

TUPOT001	Plans for Laser Ablation of Actinides into an ECRIS for Accelerator Mass Spectroscopy	ion, laser, ECR, ion-source	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]

TUPOT005	An ECR Table Plasma Generator	plasma, ECR, ion, 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]

TUPOT010	Effects of Microwave Frequency Fine Tuning on the Performance of JYFL 14 GHz ECRIS	plasma, ion, ion-source, emittance	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]

TUPOT011	Measurement of the Diamagnetic Current on the LBNL 6.4 GHz ECR Ion Source	plasma, ECR, electron, ion-source	140
	J.D. Noland, J.Y. Benitez, M. Kireeff Covo, D. Leitner, C.M. Lyneis LBNL, Berkeley, California, USA O.A. Tarvainen JYFL, Jyväskylä, Finland J. Verboncoeur UCB, Berkeley, California, USA
	Two standard plasma diagnostics (x-ray spectroscopy and measurement of the diamagnetic current) have been employed at the LBNL 6.4 GHz ECR. These diagnostics are combined with time resolved current measurements to study the plasma breakdown, build up and decay times, as well as electron heating. Individual charged particles in a magnetized plasma orbit in such a way that the magnetic field produced by their motion opposes any externally applied magnetic field. When a charged particle density gradient exists in a plasma, a net current arises. This “diamagnetic” current is proportional to the time-rate-of-change of the perpendicular component of the plasma pressure, and can be measured with a loop of wire as the plasma ignites or decays. Another common plasma diagnostic that is used to characterize an ECR plasma is measurement of the x-ray spectra created when energetic electrons scatter off of plasma ions. The x-ray spectra provide insight on the relative abundance of electrons of different energies, and thus the electron energy distribution function. The x-ray spectra can also be used to estimate the total x-ray power produced by the plasma. In this paper diamagnetic loop diagnostics and set-up is described in detail. In addition, diamagnetic loop and low energy x-ray measurements (few keV to 100 keV) taken on the LBNL 6.4 GHz ECR ion source are presented and discussed.
	Poster TUPOT011 [1.522 MB]

TUPOT012	Microwave Frequency Dependence of the Properties of the Ion Beam Extracted From a Caprice Type ECRIS	ion, plasma, 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]

TUPOT014	Optimized Extraction Conditions From High Power ECRIS by Dedicated Dielectric Structures	plasma, ion, extraction, electron	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	ion, 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]

WECOAK03	Studies of the ECR Plasma in the Visible Light Range	plasma, ECR, ion, 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]

WECOAK05	Maximum Bremsstrahlung Energy Versus Different Heating Limits	resonance, electron, plasma, photon	175
	H. A. Koivisto, V.P. Aho, P. Jones, P. Peura, J.H. Sarén, O.A. Tarvainen, V.A. Toivanen JYFL, Jyväskylä, Finland
	A comprehensive set of bremsstrahlung measurements have been performed at JYFL (University of Jyväskylä, Department of Physics) in order to understand the parameters affecting the time evolution of electron energy. In order to extend the understanding of electron heating, a new set of measurements with the JYFL 6.4 GHz ECRIS have been initiated to further study the parameters affecting the maximum bremsstrahlung energy. In the measurements the effect of magnetic field gradient, microwave power, plasma size and gas pressure were studied. In the analysis, main focus will be given to compare the results with different theoretical electron heating limits.
	Slides WECOAK05 [0.739 MB]

WECOBK04	Preliminary Results of Spatially Resolved ECR Ion Beam Profile Investigations	ion, extraction, ion-source, ECR	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]

THCOAK03	Dipole Magnet Optimization for High Efficiency Low Energy Beam Transport	emittance, simulation, extraction, ion	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]

THCOBK01	Concluding Remarks	ion, ion-source, ECR, plasma	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

MOCOAK02

Intense Beam Production with SuSI

ion, ECR, ion-source, 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

ion, ECR, ion-source, 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]

MOCOCK03

Design Study of a Higher Magnetic Field SC ECRIS at IMP

plasma, solenoid, sextupole, ion

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

ion, 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]

MOPOT002

Two-Chamber Configuration of the Bio-Nano ECRIS

ion, plasma, 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]

MOPOT010

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

ion, 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]

MOPOT011

DRAGON: a New 18 GHz RT ECR Ion Source with a Large Plasma Chamber

plasma, sextupole, extraction, injection

58

W. Lu, D. Xie, X.Z. Zhang, H.W. Zhao
IMP, Lanzhou, People's Republic of China
W. Lu
Graduate School of the Chinese Academy of Sciences, Beijing, People's Republic of China
L. Ruan, F.C. Song, B. Xiong, S. Yu, J. Yuan
IEE, Beijing, People's Republic of China

Building a strong radial magnetic field with a permanent hexapole magnet for an ECRIS is extremely challenging so that the conventional wisdom requires a small but not optimal plasma chamber that is typically of ID less or equal to 80 mm. A new 18 GHz RT ECR ion source, DRAGON, has been designed with a large bore permanent hexapole and source construction has begun at IMP. Its plasma chamber is of ID of 126 mm, the same as that of the superconducting ion source SECRAL, with maximum radial field strength reaching 1.5 Tesla at the plasma chamber wall. The overall magnetic strengths of DRAGON, with maximum axial fields of 2.7 Tesla at the injection and 1.3 Tesla at the extraction, are very similar to those of SECRAL operating at 18 GHz and hopefully the SECRAL performance. The source solenoid magnet coils are cooled by an evaporative coolant at about 50 degree C. In addition, the source is thickly insulated for beam extraction at 50 kV and higher voltage up to 100 kV can be explored. This article will present the design details and discussions of this new ion source.

Poster MOPOT011 [0.563 MB]

MOPOT013

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

target, ion, 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

ion, 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, ion-source, ion, 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]

MOPOT017

Tests of a New Axial Sputtering Technique in an ECRIS

plasma, ECR, ion, 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, ion-source, 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

ion, emittance, simulation, beam-transport

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]

TUCOAK04

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

ion, emittance, 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]

TUCOBK03

Time Evolution of Plasma Potential in Pulsed Operation of ECRIS

plasma, ion, electron, ion-source

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]

TUPOT001

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

ion, laser, ECR, ion-source

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]

TUPOT005

An ECR Table Plasma Generator

plasma, ECR, ion, 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]

TUPOT010

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

plasma, ion, ion-source, emittance

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]

TUPOT011

Measurement of the Diamagnetic Current on the LBNL 6.4 GHz ECR Ion Source

plasma, ECR, electron, ion-source

140

J.D. Noland, J.Y. Benitez, M. Kireeff Covo, D. Leitner, C.M. Lyneis
LBNL, Berkeley, California, USA
O.A. Tarvainen
JYFL, Jyväskylä, Finland
J. Verboncoeur
UCB, Berkeley, California, USA

Two standard plasma diagnostics (x-ray spectroscopy and measurement of the diamagnetic current) have been employed at the LBNL 6.4 GHz ECR. These diagnostics are combined with time resolved current measurements to study the plasma breakdown, build up and decay times, as well as electron heating. Individual charged particles in a magnetized plasma orbit in such a way that the magnetic field produced by their motion opposes any externally applied magnetic field. When a charged particle density gradient exists in a plasma, a net current arises. This “diamagnetic” current is proportional to the time-rate-of-change of the perpendicular component of the plasma pressure, and can be measured with a loop of wire as the plasma ignites or decays. Another common plasma diagnostic that is used to characterize an ECR plasma is measurement of the x-ray spectra created when energetic electrons scatter off of plasma ions. The x-ray spectra provide insight on the relative abundance of electrons of different energies, and thus the electron energy distribution function. The x-ray spectra can also be used to estimate the total x-ray power produced by the plasma. In this paper diamagnetic loop diagnostics and set-up is described in detail. In addition, diamagnetic loop and low energy x-ray measurements (few keV to 100 keV) taken on the LBNL 6.4 GHz ECR ion source are presented and discussed.

Poster TUPOT011 [1.522 MB]

TUPOT012

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

ion, plasma, 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]

TUPOT014

Optimized Extraction Conditions From High Power ECRIS by Dedicated Dielectric Structures

plasma, ion, extraction, electron

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

ion, 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]

WECOAK03

Studies of the ECR Plasma in the Visible Light Range

plasma, ECR, ion, 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]

WECOAK05

Maximum Bremsstrahlung Energy Versus Different Heating Limits

resonance, electron, plasma, photon

175

H. A. Koivisto, V.P. Aho, P. Jones, P. Peura, J.H. Sarén, O.A. Tarvainen, V.A. Toivanen
JYFL, Jyväskylä, Finland

A comprehensive set of bremsstrahlung measurements have been performed at JYFL (University of Jyväskylä, Department of Physics) in order to understand the parameters affecting the time evolution of electron energy. In order to extend the understanding of electron heating, a new set of measurements with the JYFL 6.4 GHz ECRIS have been initiated to further study the parameters affecting the maximum bremsstrahlung energy. In the measurements the effect of magnetic field gradient, microwave power, plasma size and gas pressure were studied. In the analysis, main focus will be given to compare the results with different theoretical electron heating limits.

Slides WECOAK05 [0.739 MB]

WECOBK04

Preliminary Results of Spatially Resolved ECR Ion Beam Profile Investigations

ion, extraction, ion-source, ECR

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]

THCOAK03

Dipole Magnet Optimization for High Efficiency Low Energy Beam Transport

emittance, simulation, extraction, ion

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]

THCOBK01

Concluding Remarks

ion, ion-source, ECR, plasma

201

T. Nakagawa
RIKEN Nishina Center, Wako, Japan

Concluding remarks kindly done by Takahide Nakagawa

Slides THCOBK01 [0.436 MB]