SRF2013 - List of Keywords (proton)

Paper	Title	Other Keywords	Page
MOIOB01	High Power Proton/Deuteron Accelerators	linac, SRF, operation, cavity	35
	J.-L. Biarrotte IPN, Orsay, France
	High power proton and deuteron linear accelerators can give rise to a large variety of scientific applications, useful for both fundamental and applied research. Thanks to the on-going efficient development of the superconducting RF technology, more and more projects based on such machines have emerged during the last 2 decades. This paper will review these existing high power proton/deuteron accelerator facilities or projects, trying in particular to emphasize in each case the various specificities and challenges related to the SRF technology.
	Slides MOIOB01 [4.474 MB]

MOP008	SUPERCONDUCTING LINAC FOR THE RISP	linac, cavity, cryomodule, ion	89
	H.J. Kim, H.J. Cha, M.O. Hyun, H.J. Jang, D. Jeon, J.D. Joo, M.J. Joung, H.C. Jung, Y. Jung, Y. Kim, M. Lee, G.-T. Park IBS, Daejeon, Republic of Korea
	The RISP (Rare Isotope Science Project) accelerator has been planned to study heavy ion of nuclear, material and medical science at the Institute for Basic Science (IBS). It can deliver ions from proton to Uranium. The facility consists of three superconducting linacs of which superconducting cavities are independently phased. Requirement of the linac design is especially high for acceleration of multiple charge beams. In this paper, we present the RISP linac design, the superconducting cavity, and cryomodule.

MOP015	Status of the SRF Development for the Project X	cavity, cryomodule, linac, SRF	117
	V.P. Yakovlev, T.T. Arkan, M.H. Awida, P. Berrutti, E. Borissov, A.C. Crawford, M.H. Foley, C.M. Ginsburg, I.V. Gonin, A. Grassellino, C.J. Grimm, S.D. Holmes, S. Kazakov, R.D. Kephart, T.N. Khabiboulline, V.A. Lebedev, A. Lunin, M. Merio, S. Nagaitsev, T.H. Nicol, Y.O. Orlov, D. Passarelli, T.J. Peterson, Y.M. Pischalnikov, O.V. Pronitchev, L. Ristori, A.M. Rowe, D.A. Sergatskov, N. Solyak, A.I. Sukhanov, I. Terechkine Fermilab, Batavia, USA
	Project X is a high intensity proton facility being developed to support a world-leading program of Intensity Frontier physics over the next two decades at Fermilab. The proposed facility is based on the SRF technology and consists of two linacs: CW linac to accelerate beam from 2.1 MeV to 3 GeV and pulsed linac accelerate 5% of the beam up to 8 GeV. In a CW linac five families of SC cavities are used: half-wave resonators (162.5 MHz); single-spoke cavities: SSR1 and SSR2 (325 MHz) and elliptical 5-cell β=0.6 and β=0.9 cavities (650 MHz). Pulsed 3-8 GeV linac linac are based on 9-cell 1.3 GHz cavities. In the paper the basic requirements and the status of development of SC accelerating cavities, auxiliaries (couplers, tuners, etc.) and cryomodules are presented as well as technology challenges caused by their specifics.

MOP065	Consolidated Design of the 17 MeV Injector for MYRRHA	cavity, rfq, linac, cryomodule	274
	D. Mäder, D. Koser, H. Podlech, A. Schempp IAP, Frankfurt am Main, Germany
	Funding: Project supported by the EU, FP7 MAX, contract No. 269565 and BMBF, contract No. 06FY7102. The MYRRHA research reactor will be an Accelerator Driven System, which demands a 2.4 MW proton beam delivered by a 600 MeV cw operated linac. The beam dynamics design of the injector has been consolidated to fulfil the requirements with respect to beam losses and quality. After a 4-rod-RFQ, four 7-gap room temperature CH cavities with a constant phase and an effective voltage of 750 keV are used to reach 4.3 MeV. Then the proton beam is accelerated to 18 MeV using six superconducting 5-gap Nb CH structures with a constant beta profile. With reducing the gradient and adjusting the phase of the twelfth CH structure the originally demanded 17 MeV can be delivered, too. Every SC CH cavity is cooled down to 2K with liquid helium in a separate cryo module. The new geometric design of the SC CH cavities improves the rigidity and reduces the electric peak field.

MOP066	Development of Compact Cryomodules Housing HWRs for High-intensity SC CW Linacs	cavity, cryomodule, linac, niobium	277
	P.N. Ostroumov, Z.A. Conway, S.M. Gerbick, M. Kedzie, M.P. Kelly, S.H. Kim, S.V. Kutsaev, R.C. Murphy, B. Mustapha, T. Reid ANL, Argonne, USA D. Berkovits Soreq NRC, Yavne, Israel S. Nagaitsev Fermilab, Batavia, USA
	Funding: This work was supported by the U.S. Department of Energy, under Contracts No. DE-AC02-06CH11357, DE-AC02-76CH03000 and ANL WFO No. 85Y47. Acceleration of high-intensity light-ion beams immediately after an RFQ requires a compact accelerating and focusing lattice with a high packing factor. We have developed a cryomodule which satisfies this requirement with eight accelerating-focusing periods for Project X at FNAL. Each focusing period consist of a 162.5-MHz SC HWR, a SC solenoid and a beam position monitor. The highly optimized EM parameters of the cavity were achieved by using double conical, hour glass like, inner and outer conductors. This design is also favorable for the beam dynamics because the short focusing periods which helps to better control the beam quality. All sub-systems of the cryomodule, except the vacuum-vessel, are in advanced stages of prototyping and testing. A similar concept has been developed for the design of several cryomodules for a 20 MeV/u proton/deuteron 200 kW linac at SNRC. These cryomodules house two types of 176 MHz half-wave resonators and require only modest modifications for the application. This paper will discuss the status of the FNAL cryomodule design and sub-system fabrication and its impact on future HWR cryomodule such as the SNRC project.

MOP081	Preliminary Studies of the Cryogenic Refrigerator and Distribution Systems for the MYRRHA Proton Linac	cryogenics, linac, cryomodule, operation	331
	T. Junquera, N.R. Chevalier, J.P. Thermeau Accelerators and Cryogenic Systems, Orsay, France L. Medeiros Romão, D. Vandeplassche SCK•CEN, Mol, Belgium H. Saugnac IPN, Orsay, France
	Funding: Work supported by the EU, FP7 MAX contract number 269565 In the framework of recent European programs (FP6-Eurotrans, FP7-MAX), the SC proton Linac for the MYRRHA project (associating an accelerator to a subcritical nuclear reactor, to be installed in the SCK•CEN at Mol-Belgium), has been extensively studied and optimized to reach strict requirements in beam power and reliability as needed for this ADS demonstrator. The linac, composed of 150 SC cavities (CH, spoke and elliptical) installed in 60 cryomodules, operates at 2K, delivering a beam power of 2.5 MW (600 MeV, 4 mA) in CW mode, will be installed in a tunnel of 240 m length. In this paper we present the evaluation of the cryogenic power requirements, a preliminary architecture of the cryogenic refrigerator system including all its major components, and preliminary proposals for the cryofluids distribution along the SC linac.

THIOD01	SRF Cavities for ADS Project in China	cavity, linac, SRF, operation	868
	Y. He, W.M. Yue, S.H. Zhang IMP, Lanzhou, People's Republic of China J.P. Dai, Z.Q. Li, Z.C. Liu, W.M. Pan IHEP, Beijing, People's Republic of China X.Y. Lu PKU, Beijing, People's Republic of China
	The driver linac for ADS project in China is full superconducting downstream of Radio Frequecy Quadrupole Accelerator. It is a key technology R&D stage of the project from 2011 to 2015. Superconducting HWR, Spoke, and elliptical cavities are all involved in the project. The prototypes of 162.5 MHz HWR010, 325 MHz Spoke012, 325 MHz Spoke021, 325 MHz Spoke040, and 650 MHz elliptical 063 are being developed at IMP and IHEP in China. A small number of HWR010 and Spoke012 have been produced and vertically tested. The first prototype of Spoke021 were tested too. The design, performances, fabrication, suface processing, and testing of all cavities will be presented in the talk. The design improvement of the cavities in the future will also be discussed.
	Slides THIOD01 [13.465 MB]

THP001	Development of a Prototype SRF Cavity for the Proton Beam Utilization Facility at Nanjing University	cavity, HOM, SRF, linac	889
	S. An, P.P. Xue PLAI, Nanjing, People's Republic of China S.Q.X. Xu, H. Z. Zhang ADS-SRF, People's Republic of China P.P. Xue, L. Zhang Chang’an University, Chang'an, People's Republic of China Z.R. Zhang Nanjing University of Aeronautics and Astronautics, Jiangning, People's Republic of China
	Nanjing University has initiated the new technology development in the field of high-energy, charged-particle beam application and fundamental sciences. A high-current proton accelerator used for the new energy, new technology and fundamental science applications platform will be the near term goal at Nanjing University. For developing the superconducting RF linac for the proton beam utilization at Nanjing University, the first 6-cell, medium-beta prototype superconducting RF cavity has been fabricated and demonstrated using Chinese vendors only. The low-power test has been completed. The vertical test will be carried out soon.

THP016	DEVELOPMENT OF THE SUPERCONDUCTING HALF WAVE RESONATOR FOR INJECTOR II IN C-ADS	cavity, niobium, simulation, linac	923
	W.M. Yue, W. Chang, S. He, Y. He, S.C. Huang, Y.L. Huang, T.C. Jiang, F.F. Wang, R.X. Wang, M.X. Xu, C. Zhang, S.H. Zhang, S.X. Zhang IMP, Lanzhou, People's Republic of China
	The Development of the Half Wave Resonator (HWR010) is based on the China ADS. The HWR010 operates at 162.5 MHz and can provide more than 0.78 MV of accelerating voltage per cavity for proton withβopt=0.10. We have designed the HWR010 in 2011. A copper model has been fabricated to test the HWR fabrication procedure. Five HWR010s have been fabricated in 2012. The HWR010s has finished the vertical testing and the Q0 is 4·10⁸ at Epeak = 45 MeV/m, and one of the HWR010s has been vertical tested with helium vessel. The slow tuner and high power coupler for this HWR have been developed and tested.

THP021	Design of the SSR021 Cavity for the Proton Accelerator Main Linac of China ADS	cavity, linac, simulation, target	939
	Z.Q. Li, Y.L. Chi, Q. Ma, W.M. Pan, Y. Sun, J.Y. Tang, Q.Y. Wang, B. Xu, X.Y. Zhang IHEP, Beijing, People's Republic of China Y. He, C. Zhang, S.H. Zhang, S.X. Zhang IMP, Lanzhou, People's Republic of China H.Y. Lin, P. Sha Institute of High Energy Physics (IHEP), Chinese Academy of Sciences, Beijing, People's Republic of China
	China ADS is a high intensity proton machine based on CW superconducting technology. It includes two injectors and one main linac. The Institute of High Energy Physics (IHEP) and the Institute of Modern Physics (IMP) of the Chinese Academy of Sciences (CAS), are responsible for developing the main linac together. This paper introduces the physics and mechanical design of the single spoke resonator (SSR021, beta021 cavity), which is used for first section of the main linac.

THP028	The Research on Spoke 0.40 Cavity	cavity, simulation, linac, superconducting-cavity	959
	P. Sha, H. Huang Institute of High Energy Physics (IHEP), Chinese Academy of Sciences, Beijing, People's Republic of China W.M. Pan, X.Y. Zhang IHEP, Beijing, People's Republic of China
	Spoke superconducting cavity can be used in the low-energy section of the proton accelerator. It has many significant advantages: compact structure, high value of R/Q, etc. The Chinese ADS (Accelerator Driven System) project will adopt many spoke cavities with 3 different β values (0.12, 0.21, 0.40). Spoke040 cavities (β=0.40) are used to increase the proton energy from 34 MeV to 178 MeV. Now the physical design of spoke040 cavity has been finished, and the machining are going on right now. The vertical test would be held at the end of this year.

THP033	Study of Balloon Spoke Cavities	cavity, TRIUMF, simulation, operation	972
	Z.Y. Yao, R.E. Laxdal, B.S. Waraich, V. Zvyagintsev TRIUMF, Canada's National Laboratory for Particle and Nuclear Physics, Vancouver, Canada R. Edinger PAVAC, Richmond, B.C., Canada
	A balloon geometry has been proposed to suppress multipacting for single spoke resonators. The design may find a useful application for proton and ion accelerator projects. TRIUMF has completed initial RF, mechanical, and fabrication studies on this special geometry for both low (β=0.12) and medium (β=0.3) β geometries. The RF properties are comparable with that of traditional spoke cavities but with improved RF efficiency in addition to the reduced multipacting. The results of electro-magnetic and structural design studies comparing the balloon geometry with traditional spoke geometries will be presented. We will also present optimization studies of the mechanical design, such as decreasing df/dp by EM field compensation as well as discussing tuning strategies and fabrication techniques.

THP066	SARAF Phase-I HWR Coupler Cooling Design	simulation, operation, linac, cavity	1073
	J. Rodnizki, Y. Ben Aliz, I. Fishman, A. Grin, Z. Horvitz, B. Kaizer, L. Weissman Soreq NRC, Yavne, Israel
	The Soreq Applied Research Accelerator Facility (SARAF) design is based on a 40 MeV 5 mA light ions superconducting RF linac. Phase I of SARAF delivers up to 2 mA CW proton beam in an energy range of 1.5-4.5 MeV. The maximum beam power that we have reached is 4.5 kW. The warming of the SARAF linac RF couplers is currently the main limiting factor for reaching higher CW beam power. The coupler cooling configuration was optimized by increasing the cold window copper braid and adding a copper braid to the top end, using CST Multiphysics and ANSYS steady state and transient solvers. The study was conducted for the heat load generated by the surface currents of a matched 4 kW forward CW power, simulated by the CST MWS FD solver. Multipacting is a known potential heat source that overheats the coupler in the vicinity of the cold window. The coupler overheat phenomena was experimentally studied as a function of DC bias voltage, and it was found that a 900 V bias reduces significantly the heating rate. As a result we expect that the beam power can be significantly increased. The long overheat period implies that optimization of the cooling configuration is still needed.

FRIOB03	Development of 650 MHz Cavities for the GeV Proton Accelerator in Project X	cavity, SRF, electron, HOM	1193
	S.S. Som, P. Bhattacharyya, A. Dutta Gupta, S. Ghosh, A. Mandal, S. Seth VECC, Kolkata, India
	Funding: DAE, Government of India Project X is a GeV range high intensity proton linear accelerator being developed at Fermilab, USA in collaboration with various American and Indian laboratories as well. In stage-1 of the project, the CW linac structures with different velocity factor (beta) accelerate proton up to 3 GeV at an average beam current of 1 mA. For acceleration from 180 to 480 MeV,the development of 650 MHz, beta 0.61, 5-cell elliptical SRF cavities has been taken up by VECC. The EM design and analysis of this cavity, carried out using 2D and 3D codes, will be discussed along with its structural and mechanical modal analysis. This design has been compared with the designs made by JLab and Fermilab. The presence of higher order modes (HOMs)for the said cavity has been thoroughly examined. The multipacting analysis will be presented using 2D code and also 3D CST Particle Studio code with due consideration of Furman model for secondary electron emission comprising of true, elastic and rediffused secondary electrons. The prototype development and low power testing of this cavity will be discussed here. The talk will be concluded with the probable SRF challenges to be faced in the development of the cavity.
	Slides FRIOB03 [39.119 MB]

FRIOB04	CERN Developments for 704 MHz Superconducting Cavities	cavity, niobium, operation, linac	1198
	O. Capatina, G. Arnau-Izquierdo, S. Atieh, I. Aviles Santillana, R. Bonomi, S. Calatroni, J.K. Chambrillon, R. Garoby, F. Gerigk, M. Guinchard, T. Junginger, M. Malabaila, L. Marques Antunes Ferreira, S. Mikulas, V. Parma, T. Renaglia, K.M. Schirm, T. Tardy, M. Therasse, A. Vacca, N. Valverde Alonso, A. Vande Craen CERN, Geneva, Switzerland F. Pillon Kraftanlagen Nukleartechnik GmbH, Heidelberg, Germany
	The Superconducting Proton Linac (SPL) is an R&D effort coordinated by CERN in partnership with other international laboratories. It is aiming at developing key technologies for the construction of a multi-megawatt proton linac based on state-of-the-art RF superconducting technology, which would serve as a driver in new physics facilities for neutrinos and/or Radioactive Ion Beam (RIB). Amongst the main objectives of this R&D effort, is the development of 704 MHz bulk niobium β=1 elliptical cavities, operating at 2 K with a maximum accelerating gradient of 25 MV/m, and the testing of a string of cavities integrated in a machine-type cryomodule. The cavity together with its helium tank had to be carefully designed in coherence with the innovative design of the cryomodule. New fabrication methods have also been explored. Five such niobium cavities and two copper cavities are in fabrication. The key design aspects are discussed, the results of the alternative fabrication methods presented and the status of the cavity manufacturing and surface preparation is detailed.
	Slides FRIOB04 [8.677 MB]

FRIOC02	ESS Elliptical Cavities and Cryomodules	cavity, HOM, cryomodule, cryogenics	1218
	G. Devanz, P. Bosland, M. Desmons, P. Hardy, F. Leseigneur, M. Luong, F. Peauger, J. Plouin, D. Roudier CEA/DSM/IRFU, France N. Bazin CEA/IRFU, Gif-sur-Yvette, France G. Costanza Lund University, Lund, Sweden G. Olivier IPN, Orsay, France
	The accelerator of the European Spallation Source (ESS) is a 5 MW proton linac to be built in Lund Sweden. Its superconducting section is composed of 3 cavity families: double spoke resonators, medium beta and high beta elliptical multicell cavities. This paper presents the electromagnetic and mechanical design of the 704.42 MHz elliptical cavities. Both elliptical famillies are housed in 4-cavity cryomodules which share a common design and set of components which will be described here.
	Slides FRIOC02 [3.475 MB]

Paper

Title

Other Keywords

Page

MOIOB01

High Power Proton/Deuteron Accelerators

linac, SRF, operation, cavity

35

J.-L. Biarrotte
IPN, Orsay, France

High power proton and deuteron linear accelerators can give rise to a large variety of scientific applications, useful for both fundamental and applied research. Thanks to the on-going efficient development of the superconducting RF technology, more and more projects based on such machines have emerged during the last 2 decades. This paper will review these existing high power proton/deuteron accelerator facilities or projects, trying in particular to emphasize in each case the various specificities and challenges related to the SRF technology.

Slides MOIOB01 [4.474 MB]

MOP008

SUPERCONDUCTING LINAC FOR THE RISP

linac, cavity, cryomodule, ion

89

H.J. Kim, H.J. Cha, M.O. Hyun, H.J. Jang, D. Jeon, J.D. Joo, M.J. Joung, H.C. Jung, Y. Jung, Y. Kim, M. Lee, G.-T. Park
IBS, Daejeon, Republic of Korea

The RISP (Rare Isotope Science Project) accelerator has been planned to study heavy ion of nuclear, material and medical science at the Institute for Basic Science (IBS). It can deliver ions from proton to Uranium. The facility consists of three superconducting linacs of which superconducting cavities are independently phased. Requirement of the linac design is especially high for acceleration of multiple charge beams. In this paper, we present the RISP linac design, the superconducting cavity, and cryomodule.

MOP015

Status of the SRF Development for the Project X

cavity, cryomodule, linac, SRF

117

V.P. Yakovlev, T.T. Arkan, M.H. Awida, P. Berrutti, E. Borissov, A.C. Crawford, M.H. Foley, C.M. Ginsburg, I.V. Gonin, A. Grassellino, C.J. Grimm, S.D. Holmes, S. Kazakov, R.D. Kephart, T.N. Khabiboulline, V.A. Lebedev, A. Lunin, M. Merio, S. Nagaitsev, T.H. Nicol, Y.O. Orlov, D. Passarelli, T.J. Peterson, Y.M. Pischalnikov, O.V. Pronitchev, L. Ristori, A.M. Rowe, D.A. Sergatskov, N. Solyak, A.I. Sukhanov, I. Terechkine
Fermilab, Batavia, USA

Project X is a high intensity proton facility being developed to support a world-leading program of Intensity Frontier physics over the next two decades at Fermilab. The proposed facility is based on the SRF technology and consists of two linacs: CW linac to accelerate beam from 2.1 MeV to 3 GeV and pulsed linac accelerate 5% of the beam up to 8 GeV. In a CW linac five families of SC cavities are used: half-wave resonators (162.5 MHz); single-spoke cavities: SSR1 and SSR2 (325 MHz) and elliptical 5-cell β=0.6 and β=0.9 cavities (650 MHz). Pulsed 3-8 GeV linac linac are based on 9-cell 1.3 GHz cavities. In the paper the basic requirements and the status of development of SC accelerating cavities, auxiliaries (couplers, tuners, etc.) and cryomodules are presented as well as technology challenges caused by their specifics.

MOP065

Consolidated Design of the 17 MeV Injector for MYRRHA

cavity, rfq, linac, cryomodule

274

D. Mäder, D. Koser, H. Podlech, A. Schempp
IAP, Frankfurt am Main, Germany

Funding: Project supported by the EU, FP7 MAX, contract No. 269565 and BMBF, contract No. 06FY7102.
The MYRRHA research reactor will be an Accelerator Driven System, which demands a 2.4 MW proton beam delivered by a 600 MeV cw operated linac. The beam dynamics design of the injector has been consolidated to fulfil the requirements with respect to beam losses and quality. After a 4-rod-RFQ, four 7-gap room temperature CH cavities with a constant phase and an effective voltage of 750 keV are used to reach 4.3 MeV. Then the proton beam is accelerated to 18 MeV using six superconducting 5-gap Nb CH structures with a constant beta profile. With reducing the gradient and adjusting the phase of the twelfth CH structure the originally demanded 17 MeV can be delivered, too. Every SC CH cavity is cooled down to 2K with liquid helium in a separate cryo module. The new geometric design of the SC CH cavities improves the rigidity and reduces the electric peak field.

MOP066

Development of Compact Cryomodules Housing HWRs for High-intensity SC CW Linacs

cavity, cryomodule, linac, niobium

277

P.N. Ostroumov, Z.A. Conway, S.M. Gerbick, M. Kedzie, M.P. Kelly, S.H. Kim, S.V. Kutsaev, R.C. Murphy, B. Mustapha, T. Reid
ANL, Argonne, USA
D. Berkovits
Soreq NRC, Yavne, Israel
S. Nagaitsev
Fermilab, Batavia, USA

Funding: This work was supported by the U.S. Department of Energy, under Contracts No. DE-AC02-06CH11357, DE-AC02-76CH03000 and ANL WFO No. 85Y47.
Acceleration of high-intensity light-ion beams immediately after an RFQ requires a compact accelerating and focusing lattice with a high packing factor. We have developed a cryomodule which satisfies this requirement with eight accelerating-focusing periods for Project X at FNAL. Each focusing period consist of a 162.5-MHz SC HWR, a SC solenoid and a beam position monitor. The highly optimized EM parameters of the cavity were achieved by using double conical, hour glass like, inner and outer conductors. This design is also favorable for the beam dynamics because the short focusing periods which helps to better control the beam quality. All sub-systems of the cryomodule, except the vacuum-vessel, are in advanced stages of prototyping and testing. A similar concept has been developed for the design of several cryomodules for a 20 MeV/u proton/deuteron 200 kW linac at SNRC. These cryomodules house two types of 176 MHz half-wave resonators and require only modest modifications for the application. This paper will discuss the status of the FNAL cryomodule design and sub-system fabrication and its impact on future HWR cryomodule such as the SNRC project.

MOP081

Preliminary Studies of the Cryogenic Refrigerator and Distribution Systems for the MYRRHA Proton Linac

cryogenics, linac, cryomodule, operation

331

T. Junquera, N.R. Chevalier, J.P. Thermeau
Accelerators and Cryogenic Systems, Orsay, France
L. Medeiros Romão, D. Vandeplassche
SCK•CEN, Mol, Belgium
H. Saugnac
IPN, Orsay, France

Funding: Work supported by the EU, FP7 MAX contract number 269565
In the framework of recent European programs (FP6-Eurotrans, FP7-MAX), the SC proton Linac for the MYRRHA project (associating an accelerator to a subcritical nuclear reactor, to be installed in the SCK•CEN at Mol-Belgium), has been extensively studied and optimized to reach strict requirements in beam power and reliability as needed for this ADS demonstrator. The linac, composed of 150 SC cavities (CH, spoke and elliptical) installed in 60 cryomodules, operates at 2K, delivering a beam power of 2.5 MW (600 MeV, 4 mA) in CW mode, will be installed in a tunnel of 240 m length. In this paper we present the evaluation of the cryogenic power requirements, a preliminary architecture of the cryogenic refrigerator system including all its major components, and preliminary proposals for the cryofluids distribution along the SC linac.

THIOD01

SRF Cavities for ADS Project in China

cavity, linac, SRF, operation

868

Y. He, W.M. Yue, S.H. Zhang
IMP, Lanzhou, People's Republic of China
J.P. Dai, Z.Q. Li, Z.C. Liu, W.M. Pan
IHEP, Beijing, People's Republic of China
X.Y. Lu
PKU, Beijing, People's Republic of China

The driver linac for ADS project in China is full superconducting downstream of Radio Frequecy Quadrupole Accelerator. It is a key technology R&D stage of the project from 2011 to 2015. Superconducting HWR, Spoke, and elliptical cavities are all involved in the project. The prototypes of 162.5 MHz HWR010, 325 MHz Spoke012, 325 MHz Spoke021, 325 MHz Spoke040, and 650 MHz elliptical 063 are being developed at IMP and IHEP in China. A small number of HWR010 and Spoke012 have been produced and vertically tested. The first prototype of Spoke021 were tested too. The design, performances, fabrication, suface processing, and testing of all cavities will be presented in the talk. The design improvement of the cavities in the future will also be discussed.

Slides THIOD01 [13.465 MB]

THP001

Development of a Prototype SRF Cavity for the Proton Beam Utilization Facility at Nanjing University

cavity, HOM, SRF, linac

889

S. An, P.P. Xue
PLAI, Nanjing, People's Republic of China
S.Q.X. Xu, H. Z. Zhang
ADS-SRF, People's Republic of China
P.P. Xue, L. Zhang
Chang’an University, Chang'an, People's Republic of China
Z.R. Zhang
Nanjing University of Aeronautics and Astronautics, Jiangning, People's Republic of China

Nanjing University has initiated the new technology development in the field of high-energy, charged-particle beam application and fundamental sciences. A high-current proton accelerator used for the new energy, new technology and fundamental science applications platform will be the near term goal at Nanjing University. For developing the superconducting RF linac for the proton beam utilization at Nanjing University, the first 6-cell, medium-beta prototype superconducting RF cavity has been fabricated and demonstrated using Chinese vendors only. The low-power test has been completed. The vertical test will be carried out soon.

THP016

DEVELOPMENT OF THE SUPERCONDUCTING HALF WAVE RESONATOR FOR INJECTOR II IN C-ADS

cavity, niobium, simulation, linac

923

W.M. Yue, W. Chang, S. He, Y. He, S.C. Huang, Y.L. Huang, T.C. Jiang, F.F. Wang, R.X. Wang, M.X. Xu, C. Zhang, S.H. Zhang, S.X. Zhang
IMP, Lanzhou, People's Republic of China

The Development of the Half Wave Resonator (HWR010) is based on the China ADS. The HWR010 operates at 162.5 MHz and can provide more than 0.78 MV of accelerating voltage per cavity for proton withβopt=0.10. We have designed the HWR010 in 2011. A copper model has been fabricated to test the HWR fabrication procedure. Five HWR010s have been fabricated in 2012. The HWR010s has finished the vertical testing and the Q0 is 4·10⁸ at Epeak = 45 MeV/m, and one of the HWR010s has been vertical tested with helium vessel. The slow tuner and high power coupler for this HWR have been developed and tested.

THP021

Design of the SSR021 Cavity for the Proton Accelerator Main Linac of China ADS

cavity, linac, simulation, target

939

Z.Q. Li, Y.L. Chi, Q. Ma, W.M. Pan, Y. Sun, J.Y. Tang, Q.Y. Wang, B. Xu, X.Y. Zhang
IHEP, Beijing, People's Republic of China
Y. He, C. Zhang, S.H. Zhang, S.X. Zhang
IMP, Lanzhou, People's Republic of China
H.Y. Lin, P. Sha
Institute of High Energy Physics (IHEP), Chinese Academy of Sciences, Beijing, People's Republic of China

China ADS is a high intensity proton machine based on CW superconducting technology. It includes two injectors and one main linac. The Institute of High Energy Physics (IHEP) and the Institute of Modern Physics (IMP) of the Chinese Academy of Sciences (CAS), are responsible for developing the main linac together. This paper introduces the physics and mechanical design of the single spoke resonator (SSR021, beta021 cavity), which is used for first section of the main linac.

THP028

The Research on Spoke 0.40 Cavity

cavity, simulation, linac, superconducting-cavity

959

P. Sha, H. Huang
Institute of High Energy Physics (IHEP), Chinese Academy of Sciences, Beijing, People's Republic of China
W.M. Pan, X.Y. Zhang
IHEP, Beijing, People's Republic of China

Spoke superconducting cavity can be used in the low-energy section of the proton accelerator. It has many significant advantages: compact structure, high value of R/Q, etc. The Chinese ADS (Accelerator Driven System) project will adopt many spoke cavities with 3 different β values (0.12, 0.21, 0.40). Spoke040 cavities (β=0.40) are used to increase the proton energy from 34 MeV to 178 MeV. Now the physical design of spoke040 cavity has been finished, and the machining are going on right now. The vertical test would be held at the end of this year.

THP033

Study of Balloon Spoke Cavities

cavity, TRIUMF, simulation, operation

972

Z.Y. Yao, R.E. Laxdal, B.S. Waraich, V. Zvyagintsev
TRIUMF, Canada's National Laboratory for Particle and Nuclear Physics, Vancouver, Canada
R. Edinger
PAVAC, Richmond, B.C., Canada

A balloon geometry has been proposed to suppress multipacting for single spoke resonators. The design may find a useful application for proton and ion accelerator projects. TRIUMF has completed initial RF, mechanical, and fabrication studies on this special geometry for both low (β=0.12) and medium (β=0.3) β geometries. The RF properties are comparable with that of traditional spoke cavities but with improved RF efficiency in addition to the reduced multipacting. The results of electro-magnetic and structural design studies comparing the balloon geometry with traditional spoke geometries will be presented. We will also present optimization studies of the mechanical design, such as decreasing df/dp by EM field compensation as well as discussing tuning strategies and fabrication techniques.

THP066

SARAF Phase-I HWR Coupler Cooling Design

simulation, operation, linac, cavity

1073

J. Rodnizki, Y. Ben Aliz, I. Fishman, A. Grin, Z. Horvitz, B. Kaizer, L. Weissman
Soreq NRC, Yavne, Israel

The Soreq Applied Research Accelerator Facility (SARAF) design is based on a 40 MeV 5 mA light ions superconducting RF linac. Phase I of SARAF delivers up to 2 mA CW proton beam in an energy range of 1.5-4.5 MeV. The maximum beam power that we have reached is 4.5 kW. The warming of the SARAF linac RF couplers is currently the main limiting factor for reaching higher CW beam power. The coupler cooling configuration was optimized by increasing the cold window copper braid and adding a copper braid to the top end, using CST Multiphysics and ANSYS steady state and transient solvers. The study was conducted for the heat load generated by the surface currents of a matched 4 kW forward CW power, simulated by the CST MWS FD solver. Multipacting is a known potential heat source that overheats the coupler in the vicinity of the cold window. The coupler overheat phenomena was experimentally studied as a function of DC bias voltage, and it was found that a 900 V bias reduces significantly the heating rate. As a result we expect that the beam power can be significantly increased. The long overheat period implies that optimization of the cooling configuration is still needed.

FRIOB03

Development of 650 MHz Cavities for the GeV Proton Accelerator in Project X

cavity, SRF, electron, HOM

1193

S.S. Som, P. Bhattacharyya, A. Dutta Gupta, S. Ghosh, A. Mandal, S. Seth
VECC, Kolkata, India

Funding: DAE, Government of India
Project X is a GeV range high intensity proton linear accelerator being developed at Fermilab, USA in collaboration with various American and Indian laboratories as well. In stage-1 of the project, the CW linac structures with different velocity factor (beta) accelerate proton up to 3 GeV at an average beam current of 1 mA. For acceleration from 180 to 480 MeV,the development of 650 MHz, beta 0.61, 5-cell elliptical SRF cavities has been taken up by VECC. The EM design and analysis of this cavity, carried out using 2D and 3D codes, will be discussed along with its structural and mechanical modal analysis. This design has been compared with the designs made by JLab and Fermilab. The presence of higher order modes (HOMs)for the said cavity has been thoroughly examined. The multipacting analysis will be presented using 2D code and also 3D CST Particle Studio code with due consideration of Furman model for secondary electron emission comprising of true, elastic and rediffused secondary electrons. The prototype development and low power testing of this cavity will be discussed here. The talk will be concluded with the probable SRF challenges to be faced in the development of the cavity.

Slides FRIOB03 [39.119 MB]

FRIOB04

CERN Developments for 704 MHz Superconducting Cavities

cavity, niobium, operation, linac

1198

O. Capatina, G. Arnau-Izquierdo, S. Atieh, I. Aviles Santillana, R. Bonomi, S. Calatroni, J.K. Chambrillon, R. Garoby, F. Gerigk, M. Guinchard, T. Junginger, M. Malabaila, L. Marques Antunes Ferreira, S. Mikulas, V. Parma, T. Renaglia, K.M. Schirm, T. Tardy, M. Therasse, A. Vacca, N. Valverde Alonso, A. Vande Craen
CERN, Geneva, Switzerland
F. Pillon
Kraftanlagen Nukleartechnik GmbH, Heidelberg, Germany

The Superconducting Proton Linac (SPL) is an R&D effort coordinated by CERN in partnership with other international laboratories. It is aiming at developing key technologies for the construction of a multi-megawatt proton linac based on state-of-the-art RF superconducting technology, which would serve as a driver in new physics facilities for neutrinos and/or Radioactive Ion Beam (RIB). Amongst the main objectives of this R&D effort, is the development of 704 MHz bulk niobium β=1 elliptical cavities, operating at 2 K with a maximum accelerating gradient of 25 MV/m, and the testing of a string of cavities integrated in a machine-type cryomodule. The cavity together with its helium tank had to be carefully designed in coherence with the innovative design of the cryomodule. New fabrication methods have also been explored. Five such niobium cavities and two copper cavities are in fabrication. The key design aspects are discussed, the results of the alternative fabrication methods presented and the status of the cavity manufacturing and surface preparation is detailed.

Slides FRIOB04 [8.677 MB]

FRIOC02

ESS Elliptical Cavities and Cryomodules

cavity, HOM, cryomodule, cryogenics

1218

G. Devanz, P. Bosland, M. Desmons, P. Hardy, F. Leseigneur, M. Luong, F. Peauger, J. Plouin, D. Roudier
CEA/DSM/IRFU, France
N. Bazin
CEA/IRFU, Gif-sur-Yvette, France
G. Costanza
Lund University, Lund, Sweden
G. Olivier
IPN, Orsay, France

The accelerator of the European Spallation Source (ESS) is a 5 MW proton linac to be built in Lund Sweden. Its superconducting section is composed of 3 cavity families: double spoke resonators, medium beta and high beta elliptical multicell cavities. This paper presents the electromagnetic and mechanical design of the 704.42 MHz elliptical cavities. Both elliptical famillies are housed in 4-cavity cryomodules which share a common design and set of components which will be described here.

Slides FRIOC02 [3.475 MB]