Cyclotrons2013 - List of Keywords (emittance)

Paper	Title	Other Keywords	Page
MOPPT007	Recent Progress at the Jyväskylä Cyclotron Laboratory	cyclotron, ion, ion-source, quadrupole	43
	P. M.T. Heikkinen JYFL, Jyväskylä, Finland
	The use of the K130 cyclotron during the past few years has been normal. The total use of the cyclotron in 2012 was 6441 hours out of which 4610 hours on target. Three quarters of the beam time was devoted to basic nuclear physics research and one quarter for industrial applications, the main industrial application being space electronics testing. Altogether over 20 different isotopes were accelerated in 2012. Beam cocktails for space electronics testing were the most commonly used beams (26 %). Since the first beam in 1992 the total run time for the K130 cyclotron at the end of 2012 was 124’138 hours, and altogether 32 elements (73 isotopes) from p to Au have been accelerated. The MCC30/15 cyclotron will deliver proton and deuteron beams for nuclear physics research and for isotope production. The experimental set-up has been mainly under construction and we have had only a couple of beam tests. Isotope production with the MCC30/15 cyclotron has suffered from severe administrative delays. Finally in December 2012 a preliminary budget study for a GMP laboratory for FDG production (18F) was done. Decisions on the radiopharmaceuticals production at JYFL will be done during 2013.

MO4PB03	Advanced FFAG Optics, Design and Experiment	acceleration, insertion, betatron, linac	120
	J.-B. Lagrange, Y. Mori Kyoto University, Research Reactor Institute, Osaka, Japan
	Much progress has been made in the FFAG design with novel ideas, for example, FFAG straight line, FFAG with race track shape, FFAG with vertical orbit excursion, etc. Some of these were demonstrated experimentally. The talk will review the recent progress around the world.
	Slides MO4PB03 [13.272 MB]

TU1PB04	Status of the RIKEN 28-GHz SC-ECRIS	ion, ion-source, ECR, heavy-ion	139
	Y. Higurashi, M. Kidera, T. Nakagawa, J. Ohnishi, K. Ozeki RIKEN Nishina Center, Wako, Japan
	Since we obtained first beam from RIKEN 28GHz SC-ECRIS in 2009, we tried to increase the beam intensity using various methods. Recently, we observed that the use of Al chamber strongly enhanced the beam intensity of highly charged U ion beam. Using this method, we obtained ~180e μA of U³⁵⁺ and ~230e μA of U³³⁺ at the injected RF power of ~3kW with sputtering method. Advantage of this method is that we can insert the large amount of material into the plasma chamber, therefore, we can produce the beam for long term without break. Actually, we already produced intense U beams for the RIBF experiments longer than month without break. For the long term operation, we observed that the consumption rate of the U metal was ~4mg/h. In this spring, we also produced U beam with high temperature oven and two frequencies injection. In these test experiments, we observed that the beam intensity of highly charged U ions is strongly enhanced. In this contribution, we report the various results of the test experiments for production of highly charged U ion beam. We also report the experience of the long term production of the U ion beam for RIKEN RIBF experiments.
	Slides TU1PB04 [6.949 MB]

TUPPT009	Development of Rapid Emittance Measurement System	ion, ion-source, controls, cyclotron	171
	K. Kamakura, M. Fukuda, N. Hamatani, K. Hatanaka, M. Kibayashi, S. Morinobu, K. Nagayama, T. Saito, H. Tamura, H. Ueda, H. Yamamoto, Y. Yasuda, T. Yorita RCNP, Osaka, Japan
	We have developed a new system to measure the beam emittance. With our conventional emittance measurement system, it takes about 30 minutes to get emittances in both the horizontal and vertical plane. For quick measurements, we have developed a new system consisting of a fast moving slit with a fixed width and a BPM83 (rotating wire beam profile monitor). BPM83 uses a rotating helical wire made of tungsten, the speed is 18 rps. Fast moving slit consists of a shielding plate with two slits, and is inserted into the beam path at an angle of 45 degrees. The slit is driven by PLC controlled stepping motor, and it takes 70 seconds to move the full stroke of 290 mm. While moving the slit, the output from BPM83 and the voltage of potentiometer that corresponds to the slit position are recorded simultaneously. We are using CAMAC for data acquisition. Trigger signals are generated by BPM83 and NIM modules. Data analysis takes about 1 second. With this system we can get the horizontal and vertical emittance plots within 75 seconds. This system will definitely make it easier to optimize parameters of ion sources and the beam transport system.

TUPPT016	Developments of Ion Source Complex for Highly Intense Beam at RCNP	extraction, ion, ECR, plasma	189
	T. Yorita, M. Fukuda, K. Hatanaka, K. Kamakura, S. Morinobu, A. Tamii, H. Ueda, Y. Yasuda RCNP, Osaka, Japan
	Several developments of Ion Source Complex at RCNP has been carried for the purpose of increasing beam intensity. For an 18 GHz superconducting ECRIS, studies for its beam extraction and transportation have been done. The parameters of extraction systems and electrostatic lens are optimized taking account with magnetic field leakage from AVF Cyclotron. HIP-ECR the 2.45GHz permanent magnet ECR has also been developed for highly intense proton beam.

TUPPT022	A 20 mA H⁻ Ion Source with Accel-Accel-Decel Extraction System at TRIUMF	extraction, ion-source, ion, TRIUMF	198
	K. Jayamanna, I. Aguilar, I.V. Bylinskii, G. Cojocaru, R.L. Dube, R.K. Laplante, W. L. Louie, M. Lovera, M. Minato, M. Mouat, S. Saminathan, T.M. Tateyama, E. Tikhomolov TRIUMF, Canada's National Laboratory for Particle and Nuclear Physics, Vancouver, Canada
	During the last three decades, TRIUMF has developed H⁻ cusp ion sources for the 500 MeV, TR30, TR13 cyclotrons, as well as many other machines. These ion sources can be categorized as high current versions, producing up to 20mA of CW H⁻ beam within a normalized emittance (4RMS) of 0.6 π-mm-mrad. A new accel-accel-decel extraction system is being developed in order to run the source at optimum source extraction voltage for a large range of beam energies with minimal impact on beam properties. With this extraction system, beam energy can be as low as ~1keV and as high as 60keV while source extraction voltage can be at its optimum within 90kV. The source performances, as well as relevant emittance measurements, are discussed.

WE2PB01	Space Charge Limit in Separated Turn Cyclotrons	space-charge, cyclotron, extraction, TRIUMF	305
	R.A. Baartman TRIUMF, Canada's National Laboratory for Particle and Nuclear Physics, Vancouver, Canada
	A review will be given of the intensity limits of cyclotrons due to space charge, both longitudinal and transverse.
	Slides WE2PB01 [1.513 MB]

WE2PB03	Transverse-Longitudinal Coupling by Space Charge in Cyclotrons	space-charge, cyclotron, focusing, simulation	315
	C. Baumgarten PSI, Villigen PSI, Switzerland
	Based on a linear space charge model and on the results of PIC-simulations with OPAL, we analyze the conditions under which space charge forces support bunch compactness in high intensity cyclotrons and/or FFAGs. For this purpose we compare the simulated emittance increase and halo formation for different matched and mismatched particle distributions injected into a separate sector cyclotron with different phase curves.
	Slides WE2PB03 [3.187 MB]

WEPPT004	Feasibility Study of Intense Beam Matching at the Spiral Inflector Using Elliptical Solenoid	solenoid, focusing, space-charge, injection	326
	A. Goswami, V.S. Pandit, P. Sing Babu VECC, Kolkata, India
	Simulation results on a spiral inflector for compact cyclotron, indicate that convergent phase ellipses with different orientations in x and y planes and a comparatively smaller width in the y plane gives better beam transmission through the inflector. In order to transform the axisymmetric beam to a non-axisymmetric beam for matching at the entrance of the inflector one needs either an elliptical solenoid or a quadrupole doublet. The injection system of 10MeV-5mA proton cyclotron being developed at VECC consists of a 2.45GHz (80keV) microwave ion source and two solenoids to transport and match the beam at the spiral inflector. Due to space constraint we have planned to use an elliptical solenoid just before the spiral inflector for transverse matching of the beam. In this work the beam optical properties of an elliptical solenoid have been studied, including the effect of space charge. An envelope model based on the canonical description of motion has been developed and utilized to study the feasibility of using an elliptical solenoid for transverse matching of a space charge dominated beam to the acceptance of a spiral inflector.

WEPPT005	Emittance Measurements at the Strasbourg TR24 Cyclotron for the Addition of a 65 MeV Linac Booster	cyclotron, linac, proton, extraction	329
	A. Degiovanni, U. Amaldi, S. Benedetti, D. Bergesio, A. Garonna, G. Molinari TERA, Novara, Italy S. Braccini, E.V. Kirillova LHEP, Bern, Switzerland D. Brasse, M. Pellicioli, M. Rousseau, J. Schuler IPHC, Strasbourg Cedex 2, France R.L. Watt, E. van Lier ACSI, Richmond, B.C., Canada
	The long term plans of IPHC foresee the installation of a linac that will boost the energy of the protons of the Strasbourg TR24 from 24 MeV to 65 MeV. The 3 GHz Cell Coupled Linac, designed by the TERA Foundation, will be 5 meters long and will be powered by two 10 MW klystrons running at 100 Hz. Advanced Cyclotron Systems will modify the cyclotron source, so that the extracted 300 μA beam will be chopped in 4 μs long pulses. To compute the transverse acceptances of the linac, the horizontal and vertical emittances of the extracted proton beam have been measured with the secondary emission detector BISE (Beam Imaging with Secondary Electrons) built by TERA and previously calibrated at the Bern 18 MeV IBA cyclotron. In this detector a thin 5 cm diameter foil is placed at 45° with respect to the beam direction and an electrostatic lens images the secondary electrons -extracted by the protons- on a phosphor, which is viewed by a CCD camera. The results of the measurements of the transverse emittances will be reported together with the description of the linac structure and the calculation of the expected output current based on the dynamics of the accelerated proton beam.

WEPPT009	Transverse Phase-Space Distributions of Low Energy Ion Beams Extracted from an ECR Ion Source	ion, ion-source, simulation, extraction	341
	S. Saminathan TRIUMF, Canada's National Laboratory for Particle and Nuclear Physics, Vancouver, Canada J.P.M. Beijers, S. Brandenburg, H.R. Kremers, V. Mironov KVI, Groningen, The Netherlands
	Transverse phase-space distributions of low-energy ion beams extracted from ECR ion sources often show higher-order effects caused by ion-optical aberrations. Understanding these effects is mandatory to keep emittance growth and the resulting beam losses in low-energy beam transport lines under control. We present the results of an experimental and theoretical study of beam extraction and transport in the AGOR injection line at KVI. Particle tracking simulations have been performed of a multi-component neon ion beam extracted from an ECR ion source to calculate 4D phase-space distributions at various positions along the beamline. The simulations compare well with beam profile and emittance measurements.

WEPPT019	Investigation on the Transverse Emittance Growth of Intense Beam during Bunching	bunching, simulation, space-charge, solenoid	361
	P. Sing Babu, A. Goswami, V.S. Pandit VECC, Kolkata, India
	Bunchers are widely used in the injection system of cyclotrons to transform dc beam into a bunched beam in a desired phase width. In the case of low beam current, the longitudinal compression of beam has very little effect on the transverse dynamics. However in the case of high current bunching the increase of current in the specified bunch width as the beam advances affects the transverse behavior. A 2D particle-in-cell code has been developed to study the transverse dynamics during beam bunching in the injection system of 10MeV, 5mA compact proton cyclotron. We have used a linear increase of beam current in the specified bunch width from the buncher position to the time focus. In the PIC method this effect is introduced by reweighting the charge and mass of the macroparticles during the transport with longitudinal compression. The evolutions of beam envelope and emittance growth have been estimated for various initial particle distributions. It is observed that the rms beam size is independent of particular beam distribution whereas rms emittance grows with nonuniformity of the distribution and peaks near the time focus.

WEPPT026	Cyclotron Injection Tests of High-Intensity H²⁺ Beam	proton, cyclotron, solenoid, injection	372
	F.S. Labrecque, B.F. Milton BCSI, Vancouver, BC, Canada J.R. Alonso, D. Campo, J.M. Conrad, M. Toups MIT, Cambridge, Massachusetts, USA L. Calabretta, L. Celona INFN/LNS, Catania, Italy R. Gutierrez-Martinez, L.A. Winslow UCLA, Los Angeles, USA D. Winklehner NSCL, East Lansing, Michigan, USA
	Funding: Work funded by NSF agency, contract PHY-1148134 The IsoDAR (sterile neutrino) and DAEδALUS (CP-violation in neutrino sector) experiments will use cyclotrons to deliver high intensity (10 mA peak current) proton beams to neutrino-producing targets. To achieve these very high currents, we plan to inject and accelerate molecular H²⁺ ions. To understand high intensity H²⁺ injection into the central region of a compact cyclotron, and to benchmark space-charge dominated simulation studies, central-region tests are being conducted. The first test was completed this summer; a collaboration of MIT, BEST Cyclotrons and INFN-LNS at the BEST shops in Vancouver. The LNS Versatile Ion Source (VIS) was shipped from Catania to Vancouver, and was mounted, along with HV components and first focusing solenoid, on a test bench. In addition to the bench, BEST provided further beam line elements, instrumentation and a test cyclotron magnet for acceleration to no greater than 1 MeV/amu (to avoid any neutron production). Axial injection studies were conducted with a Catania-designed spiral inflector. Experimental configurations, beam characterization measurements, and phase acceptance and buncher efficiency studies will be reported.

WEPPT031	High Intensity Beam Studies Using the KURRI FFAGs	scattering, space-charge, synchrotron, injection	387
	S. Machida, C. Gabor, D.J. Kelliher, C.R. Prior, C.T. Rogers, S.L. Sheehy STFC/RAL/ASTeC, Chilton, Didcot, Oxon, United Kingdom Y. Ishi, J.-B. Lagrange, Y. Mori, T. Uesugi Kyoto University, Research Reactor Institute, Osaka, Japan
	Increasing the repetition rate of FFAG accelerators is one way of obtaining high average beam current. However, in order to achieve beam powers of up to 10 MW for applications like ADSR, the number of particles per bunch has to be approximately the same order in an FFAG as in a high power synchrotron. Collective effects such as space charge then become crucial issues. To understand high current beam behaviour in FFAGs, an international collaboration has been established to carry out an experimental programme using the FFAGs at Kyoto University's Research Reactor Institute, KURRI. The goal is to demonstrate acceleration of high bunch charge and identify the fundamental limitations. In this paper, we will show simulation results toward the first beam experiment which is planned for later in 2013.

WE3PB01	Experimental Study of Resonance Crossing with a Paul Trap	resonance, simulation, ion, plasma	409
	H. Sugimoto KEK, Ibaraki, Japan
	The effect of resonance crossing on beam stability is studied systematically by employing a novel tabletop experimental tool and a multiparticle simulation code. A large number of ions are confined in a compact linear Paul trap to reproduce the collective beam behavior. We can prove that the ion plasma in the trap is physically equivalent to a charged-particle beam propagating through a strong focusing channel. The plasma confinement force is quickly ramped such that the trap operating point traverses linear and nonlinear resonance stop bands as in cyclotrons and FFAGs.
	Slides WE3PB01 [9.757 MB]

Paper

Title

Other Keywords

Page

MOPPT007

Recent Progress at the Jyväskylä Cyclotron Laboratory

cyclotron, ion, ion-source, quadrupole

43

P. M.T. Heikkinen
JYFL, Jyväskylä, Finland

The use of the K130 cyclotron during the past few years has been normal. The total use of the cyclotron in 2012 was 6441 hours out of which 4610 hours on target. Three quarters of the beam time was devoted to basic nuclear physics research and one quarter for industrial applications, the main industrial application being space electronics testing. Altogether over 20 different isotopes were accelerated in 2012. Beam cocktails for space electronics testing were the most commonly used beams (26 %). Since the first beam in 1992 the total run time for the K130 cyclotron at the end of 2012 was 124’138 hours, and altogether 32 elements (73 isotopes) from p to Au have been accelerated. The MCC30/15 cyclotron will deliver proton and deuteron beams for nuclear physics research and for isotope production. The experimental set-up has been mainly under construction and we have had only a couple of beam tests. Isotope production with the MCC30/15 cyclotron has suffered from severe administrative delays. Finally in December 2012 a preliminary budget study for a GMP laboratory for FDG production (18F) was done. Decisions on the radiopharmaceuticals production at JYFL will be done during 2013.

MO4PB03

Advanced FFAG Optics, Design and Experiment

acceleration, insertion, betatron, linac

120

J.-B. Lagrange, Y. Mori
Kyoto University, Research Reactor Institute, Osaka, Japan

Much progress has been made in the FFAG design with novel ideas, for example, FFAG straight line, FFAG with race track shape, FFAG with vertical orbit excursion, etc. Some of these were demonstrated experimentally. The talk will review the recent progress around the world.

Slides MO4PB03 [13.272 MB]

TU1PB04

Status of the RIKEN 28-GHz SC-ECRIS

ion, ion-source, ECR, heavy-ion

139

Y. Higurashi, M. Kidera, T. Nakagawa, J. Ohnishi, K. Ozeki
RIKEN Nishina Center, Wako, Japan

Since we obtained first beam from RIKEN 28GHz SC-ECRIS in 2009, we tried to increase the beam intensity using various methods. Recently, we observed that the use of Al chamber strongly enhanced the beam intensity of highly charged U ion beam. Using this method, we obtained ~180e μA of U³⁵⁺ and ~230e μA of U³³⁺ at the injected RF power of ~3kW with sputtering method. Advantage of this method is that we can insert the large amount of material into the plasma chamber, therefore, we can produce the beam for long term without break. Actually, we already produced intense U beams for the RIBF experiments longer than month without break. For the long term operation, we observed that the consumption rate of the U metal was ~4mg/h. In this spring, we also produced U beam with high temperature oven and two frequencies injection. In these test experiments, we observed that the beam intensity of highly charged U ions is strongly enhanced. In this contribution, we report the various results of the test experiments for production of highly charged U ion beam. We also report the experience of the long term production of the U ion beam for RIKEN RIBF experiments.

Slides TU1PB04 [6.949 MB]

TUPPT009

Development of Rapid Emittance Measurement System

ion, ion-source, controls, cyclotron

171

K. Kamakura, M. Fukuda, N. Hamatani, K. Hatanaka, M. Kibayashi, S. Morinobu, K. Nagayama, T. Saito, H. Tamura, H. Ueda, H. Yamamoto, Y. Yasuda, T. Yorita
RCNP, Osaka, Japan

We have developed a new system to measure the beam emittance. With our conventional emittance measurement system, it takes about 30 minutes to get emittances in both the horizontal and vertical plane. For quick measurements, we have developed a new system consisting of a fast moving slit with a fixed width and a BPM83 (rotating wire beam profile monitor). BPM83 uses a rotating helical wire made of tungsten, the speed is 18 rps. Fast moving slit consists of a shielding plate with two slits, and is inserted into the beam path at an angle of 45 degrees. The slit is driven by PLC controlled stepping motor, and it takes 70 seconds to move the full stroke of 290 mm. While moving the slit, the output from BPM83 and the voltage of potentiometer that corresponds to the slit position are recorded simultaneously. We are using CAMAC for data acquisition. Trigger signals are generated by BPM83 and NIM modules. Data analysis takes about 1 second. With this system we can get the horizontal and vertical emittance plots within 75 seconds. This system will definitely make it easier to optimize parameters of ion sources and the beam transport system.

TUPPT016

Developments of Ion Source Complex for Highly Intense Beam at RCNP

extraction, ion, ECR, plasma

189

T. Yorita, M. Fukuda, K. Hatanaka, K. Kamakura, S. Morinobu, A. Tamii, H. Ueda, Y. Yasuda
RCNP, Osaka, Japan

Several developments of Ion Source Complex at RCNP has been carried for the purpose of increasing beam intensity. For an 18 GHz superconducting ECRIS, studies for its beam extraction and transportation have been done. The parameters of extraction systems and electrostatic lens are optimized taking account with magnetic field leakage from AVF Cyclotron. HIP-ECR the 2.45GHz permanent magnet ECR has also been developed for highly intense proton beam.

TUPPT022

A 20 mA H⁻ Ion Source with Accel-Accel-Decel Extraction System at TRIUMF

extraction, ion-source, ion, TRIUMF

198

K. Jayamanna, I. Aguilar, I.V. Bylinskii, G. Cojocaru, R.L. Dube, R.K. Laplante, W. L. Louie, M. Lovera, M. Minato, M. Mouat, S. Saminathan, T.M. Tateyama, E. Tikhomolov
TRIUMF, Canada's National Laboratory for Particle and Nuclear Physics, Vancouver, Canada

During the last three decades, TRIUMF has developed H⁻ cusp ion sources for the 500 MeV, TR30, TR13 cyclotrons, as well as many other machines. These ion sources can be categorized as high current versions, producing up to 20mA of CW H⁻ beam within a normalized emittance (4RMS) of 0.6 π-mm-mrad. A new accel-accel-decel extraction system is being developed in order to run the source at optimum source extraction voltage for a large range of beam energies with minimal impact on beam properties. With this extraction system, beam energy can be as low as ~1keV and as high as 60keV while source extraction voltage can be at its optimum within 90kV. The source performances, as well as relevant emittance measurements, are discussed.

WE2PB01

Space Charge Limit in Separated Turn Cyclotrons

space-charge, cyclotron, extraction, TRIUMF

305

R.A. Baartman
TRIUMF, Canada's National Laboratory for Particle and Nuclear Physics, Vancouver, Canada

A review will be given of the intensity limits of cyclotrons due to space charge, both longitudinal and transverse.

Slides WE2PB01 [1.513 MB]

WE2PB03

Transverse-Longitudinal Coupling by Space Charge in Cyclotrons

space-charge, cyclotron, focusing, simulation

315

C. Baumgarten
PSI, Villigen PSI, Switzerland

Based on a linear space charge model and on the results of PIC-simulations with OPAL, we analyze the conditions under which space charge forces support bunch compactness in high intensity cyclotrons and/or FFAGs. For this purpose we compare the simulated emittance increase and halo formation for different matched and mismatched particle distributions injected into a separate sector cyclotron with different phase curves.

Slides WE2PB03 [3.187 MB]

WEPPT004

Feasibility Study of Intense Beam Matching at the Spiral Inflector Using Elliptical Solenoid

solenoid, focusing, space-charge, injection

326

A. Goswami, V.S. Pandit, P. Sing Babu
VECC, Kolkata, India

Simulation results on a spiral inflector for compact cyclotron, indicate that convergent phase ellipses with different orientations in x and y planes and a comparatively smaller width in the y plane gives better beam transmission through the inflector. In order to transform the axisymmetric beam to a non-axisymmetric beam for matching at the entrance of the inflector one needs either an elliptical solenoid or a quadrupole doublet. The injection system of 10MeV-5mA proton cyclotron being developed at VECC consists of a 2.45GHz (80keV) microwave ion source and two solenoids to transport and match the beam at the spiral inflector. Due to space constraint we have planned to use an elliptical solenoid just before the spiral inflector for transverse matching of the beam. In this work the beam optical properties of an elliptical solenoid have been studied, including the effect of space charge. An envelope model based on the canonical description of motion has been developed and utilized to study the feasibility of using an elliptical solenoid for transverse matching of a space charge dominated beam to the acceptance of a spiral inflector.

WEPPT005

Emittance Measurements at the Strasbourg TR24 Cyclotron for the Addition of a 65 MeV Linac Booster

cyclotron, linac, proton, extraction

329

A. Degiovanni, U. Amaldi, S. Benedetti, D. Bergesio, A. Garonna, G. Molinari
TERA, Novara, Italy
S. Braccini, E.V. Kirillova
LHEP, Bern, Switzerland
D. Brasse, M. Pellicioli, M. Rousseau, J. Schuler
IPHC, Strasbourg Cedex 2, France
R.L. Watt, E. van Lier
ACSI, Richmond, B.C., Canada

The long term plans of IPHC foresee the installation of a linac that will boost the energy of the protons of the Strasbourg TR24 from 24 MeV to 65 MeV. The 3 GHz Cell Coupled Linac, designed by the TERA Foundation, will be 5 meters long and will be powered by two 10 MW klystrons running at 100 Hz. Advanced Cyclotron Systems will modify the cyclotron source, so that the extracted 300 μA beam will be chopped in 4 μs long pulses. To compute the transverse acceptances of the linac, the horizontal and vertical emittances of the extracted proton beam have been measured with the secondary emission detector BISE (Beam Imaging with Secondary Electrons) built by TERA and previously calibrated at the Bern 18 MeV IBA cyclotron. In this detector a thin 5 cm diameter foil is placed at 45° with respect to the beam direction and an electrostatic lens images the secondary electrons -extracted by the protons- on a phosphor, which is viewed by a CCD camera. The results of the measurements of the transverse emittances will be reported together with the description of the linac structure and the calculation of the expected output current based on the dynamics of the accelerated proton beam.

WEPPT009

Transverse Phase-Space Distributions of Low Energy Ion Beams Extracted from an ECR Ion Source

ion, ion-source, simulation, extraction

341

S. Saminathan
TRIUMF, Canada's National Laboratory for Particle and Nuclear Physics, Vancouver, Canada
J.P.M. Beijers, S. Brandenburg, H.R. Kremers, V. Mironov
KVI, Groningen, The Netherlands

Transverse phase-space distributions of low-energy ion beams extracted from ECR ion sources often show higher-order effects caused by ion-optical aberrations. Understanding these effects is mandatory to keep emittance growth and the resulting beam losses in low-energy beam transport lines under control. We present the results of an experimental and theoretical study of beam extraction and transport in the AGOR injection line at KVI. Particle tracking simulations have been performed of a multi-component neon ion beam extracted from an ECR ion source to calculate 4D phase-space distributions at various positions along the beamline. The simulations compare well with beam profile and emittance measurements.

WEPPT019

Investigation on the Transverse Emittance Growth of Intense Beam during Bunching

bunching, simulation, space-charge, solenoid

361

P. Sing Babu, A. Goswami, V.S. Pandit
VECC, Kolkata, India

Bunchers are widely used in the injection system of cyclotrons to transform dc beam into a bunched beam in a desired phase width. In the case of low beam current, the longitudinal compression of beam has very little effect on the transverse dynamics. However in the case of high current bunching the increase of current in the specified bunch width as the beam advances affects the transverse behavior. A 2D particle-in-cell code has been developed to study the transverse dynamics during beam bunching in the injection system of 10MeV, 5mA compact proton cyclotron. We have used a linear increase of beam current in the specified bunch width from the buncher position to the time focus. In the PIC method this effect is introduced by reweighting the charge and mass of the macroparticles during the transport with longitudinal compression. The evolutions of beam envelope and emittance growth have been estimated for various initial particle distributions. It is observed that the rms beam size is independent of particular beam distribution whereas rms emittance grows with nonuniformity of the distribution and peaks near the time focus.

WEPPT026

Cyclotron Injection Tests of High-Intensity H²⁺ Beam

proton, cyclotron, solenoid, injection

372

F.S. Labrecque, B.F. Milton
BCSI, Vancouver, BC, Canada
J.R. Alonso, D. Campo, J.M. Conrad, M. Toups
MIT, Cambridge, Massachusetts, USA
L. Calabretta, L. Celona
INFN/LNS, Catania, Italy
R. Gutierrez-Martinez, L.A. Winslow
UCLA, Los Angeles, USA
D. Winklehner
NSCL, East Lansing, Michigan, USA

Funding: Work funded by NSF agency, contract PHY-1148134
The IsoDAR (sterile neutrino) and DAEδALUS (CP-violation in neutrino sector) experiments will use cyclotrons to deliver high intensity (10 mA peak current) proton beams to neutrino-producing targets. To achieve these very high currents, we plan to inject and accelerate molecular H²⁺ ions. To understand high intensity H²⁺ injection into the central region of a compact cyclotron, and to benchmark space-charge dominated simulation studies, central-region tests are being conducted. The first test was completed this summer; a collaboration of MIT, BEST Cyclotrons and INFN-LNS at the BEST shops in Vancouver. The LNS Versatile Ion Source (VIS) was shipped from Catania to Vancouver, and was mounted, along with HV components and first focusing solenoid, on a test bench. In addition to the bench, BEST provided further beam line elements, instrumentation and a test cyclotron magnet for acceleration to no greater than 1 MeV/amu (to avoid any neutron production). Axial injection studies were conducted with a Catania-designed spiral inflector. Experimental configurations, beam characterization measurements, and phase acceptance and buncher efficiency studies will be reported.

WEPPT031

High Intensity Beam Studies Using the KURRI FFAGs

scattering, space-charge, synchrotron, injection

387

S. Machida, C. Gabor, D.J. Kelliher, C.R. Prior, C.T. Rogers, S.L. Sheehy
STFC/RAL/ASTeC, Chilton, Didcot, Oxon, United Kingdom
Y. Ishi, J.-B. Lagrange, Y. Mori, T. Uesugi
Kyoto University, Research Reactor Institute, Osaka, Japan

Increasing the repetition rate of FFAG accelerators is one way of obtaining high average beam current. However, in order to achieve beam powers of up to 10 MW for applications like ADSR, the number of particles per bunch has to be approximately the same order in an FFAG as in a high power synchrotron. Collective effects such as space charge then become crucial issues. To understand high current beam behaviour in FFAGs, an international collaboration has been established to carry out an experimental programme using the FFAGs at Kyoto University's Research Reactor Institute, KURRI. The goal is to demonstrate acceleration of high bunch charge and identify the fundamental limitations. In this paper, we will show simulation results toward the first beam experiment which is planned for later in 2013.

WE3PB01

Experimental Study of Resonance Crossing with a Paul Trap

resonance, simulation, ion, plasma

409

H. Sugimoto
KEK, Ibaraki, Japan

The effect of resonance crossing on beam stability is studied systematically by employing a novel tabletop experimental tool and a multiparticle simulation code. A large number of ions are confined in a compact linear Paul trap to reproduce the collective beam behavior. We can prove that the ion plasma in the trap is physically equivalent to a charged-particle beam propagating through a strong focusing channel. The plasma confinement force is quickly ramped such that the trap operating point traverses linear and nonlinear resonance stop bands as in cyclotrons and FFAGs.

Slides WE3PB01 [9.757 MB]