CYCLOTRONS 2010 - List of Keywords (space-charge)

Paper	Title	Other Keywords	Page
MOPCP038	Design Optimization of the Spiral Inflector for a High Current Compact Cyclotron	ion, cyclotron, coupling, emittance	129
	A. Goswami, V.S. Pandit, P. Sing Babu DAE/VECC, Calcutta, India
	VECC is developing a 10 MeV, 5 mA compact proton cyclotron. 80 keV protons from a 2.45 GHz microwave ion source will be injected axially in the central region by a spiral inflector. Because of the high injection energy, the inflector will be comparatively large in size. In order to avoid the beam blow up due to space charge effect and to accommodate the inflector in the small available space in the central region, the design and optimization of the inflector parameters require special attention. This paper describes the design of the spiral inflector and studies its optical properties in the presence of space charge. The beam trajectory calculation from the entrance of the spiral inflector to the central region of the cyclotron have been carried out using the magnetic field data obtained from a 3D code and the electric field data from RELAX3D. We have also checked the orbit centering of the injected beam using a central region code. We have evaluated the effect of linear space charge and carried out optimization of the input beam parameters to minimize the coupling effects between two transverse planes at the inflector exit and to match the acceptance of the central region.

MOPCP045	Towards Quantitative Predictions of High Power Cyclotrons	cyclotron, simulation, proton, extraction	144
	Y.J. Bi, J.J. Yang, T.J. Zhang CIAE, Beijing, People's Republic of China A. Adelmann, R. Dölling, J.M. Humbel, W. Joho, M. Seidel PSI, Villigen, Switzerland Y.J. Bi Tsinghua University, Beijing, People's Republic of China C.-X. Tang TUB, Beijing, People's Republic of China
	The large and complex structure of cyclotrons poses great challenges in the precise simulation of high power beams. However, such simulation capabilities are mandatory in the design and operation of the next generation high power proton drivers. The powerful tool OPAL enables us to do large scale simulations including 3D space charge and particle matter interactions. A large scale simulation effort is presented in the paper, which leads to a better quantitative understanding of the existing PSI high power proton cyclotron facility and predicts the beam behavior of CYCIAE-100 under construction at CIAE. The beam power of 1.3 MW delivered by the PSI 590 MeV Ring Cyclotron together with stringent requirements regarding the controlled and uncontrolled beam losses poses great challenges to predictive simulations. The comparisons with measurements show that OPAL can precisely predict the radial beam pattern at extraction with large dynamic range (3-4 orders of magnitude). The new particle matter interaction model is used to obtain necessary beam loss statistics during the acceleration. This data is indispensable in the design of an efficient collimation system in CYCIAE-100.

MOPCP050	Studies of ECRIS Ion Beam Formation and Quality at the Department of Physics, University of Jyväskylä	ion, ion-source, emittance, plasma	153
	V.A. Toivanen, V.P. Aho, J. Ärje, J.A. Kauppinen, H. A. Koivisto, O.A. Tarvainen JYFL, Jyväskylä, Finland L. Celona, G. Ciavola, S. Gammino, D. Mascali INFN/LNS, Catania, Italy A. Galatà INFN/LNL, Legnaro (PD), Italy T. Ropponen NSCL, East Lansing, Michigan, USA
	During the last couple of years a lot of effort has been put into studies concerning the ion beam formation and beam quality of electron cyclotron resonance ion sources (ECRISs) at the Department of Physics, University of Jyväskylä (JYFL). The effects of microwave frequency fine tuning on the performance of JYFL 14 GHz ECRIS have been studied with multiple experiments in collaboration with INFN-LNS (Instituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Sud). Also, a number of measurements have been carried out to study the effects of space charge compensation of ion beams on the beam quality. In order to proceed further with these studies, a modified version of the beam potential measurement device developed at LBNL (Lawrence Berkeley National Laboratory) is under development. Simulations are used to study the possibility to improve the beam quality by biasing the beginning of the beam line upstream from m/q separation. With high voltage biasing the beam energy could be increased temporarily over the limit of the injection system of the accelerator. Latest results and current status of these projects will be presented and discussed.

Paper

Title

Other Keywords

Page

MOPCP038

Design Optimization of the Spiral Inflector for a High Current Compact Cyclotron

ion, cyclotron, coupling, emittance

129

A. Goswami, V.S. Pandit, P. Sing Babu
DAE/VECC, Calcutta, India

VECC is developing a 10 MeV, 5 mA compact proton cyclotron. 80 keV protons from a 2.45 GHz microwave ion source will be injected axially in the central region by a spiral inflector. Because of the high injection energy, the inflector will be comparatively large in size. In order to avoid the beam blow up due to space charge effect and to accommodate the inflector in the small available space in the central region, the design and optimization of the inflector parameters require special attention. This paper describes the design of the spiral inflector and studies its optical properties in the presence of space charge. The beam trajectory calculation from the entrance of the spiral inflector to the central region of the cyclotron have been carried out using the magnetic field data obtained from a 3D code and the electric field data from RELAX3D. We have also checked the orbit centering of the injected beam using a central region code. We have evaluated the effect of linear space charge and carried out optimization of the input beam parameters to minimize the coupling effects between two transverse planes at the inflector exit and to match the acceptance of the central region.

MOPCP045

Towards Quantitative Predictions of High Power Cyclotrons

cyclotron, simulation, proton, extraction

144

Y.J. Bi, J.J. Yang, T.J. Zhang
CIAE, Beijing, People's Republic of China
A. Adelmann, R. Dölling, J.M. Humbel, W. Joho, M. Seidel
PSI, Villigen, Switzerland
Y.J. Bi
Tsinghua University, Beijing, People's Republic of China
C.-X. Tang
TUB, Beijing, People's Republic of China

The large and complex structure of cyclotrons poses great challenges in the precise simulation of high power beams. However, such simulation capabilities are mandatory in the design and operation of the next generation high power proton drivers. The powerful tool OPAL enables us to do large scale simulations including 3D space charge and particle matter interactions. A large scale simulation effort is presented in the paper, which leads to a better quantitative understanding of the existing PSI high power proton cyclotron facility and predicts the beam behavior of CYCIAE-100 under construction at CIAE. The beam power of 1.3 MW delivered by the PSI 590 MeV Ring Cyclotron together with stringent requirements regarding the controlled and uncontrolled beam losses poses great challenges to predictive simulations. The comparisons with measurements show that OPAL can precisely predict the radial beam pattern at extraction with large dynamic range (3-4 orders of magnitude). The new particle matter interaction model is used to obtain necessary beam loss statistics during the acceleration. This data is indispensable in the design of an efficient collimation system in CYCIAE-100.

MOPCP050

Studies of ECRIS Ion Beam Formation and Quality at the Department of Physics, University of Jyväskylä

ion, ion-source, emittance, plasma

153

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

During the last couple of years a lot of effort has been put into studies concerning the ion beam formation and beam quality of electron cyclotron resonance ion sources (ECRISs) at the Department of Physics, University of Jyväskylä (JYFL). The effects of microwave frequency fine tuning on the performance of JYFL 14 GHz ECRIS have been studied with multiple experiments in collaboration with INFN-LNS (Instituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Sud). Also, a number of measurements have been carried out to study the effects of space charge compensation of ion beams on the beam quality. In order to proceed further with these studies, a modified version of the beam potential measurement device developed at LBNL (Lawrence Berkeley National Laboratory) is under development. Simulations are used to study the possibility to improve the beam quality by biasing the beginning of the beam line upstream from m/q separation. With high voltage biasing the beam energy could be increased temporarily over the limit of the injection system of the accelerator. Latest results and current status of these projects will be presented and discussed.