Cyclotrons2013 - List of Keywords (acceleration)

Paper	Title	Other Keywords	Page
MO1PB01	Acceleration of Intense Heavy Ion Beams in RIBF Cascaded-Cyclotrons	ion, cyclotron, extraction, heavy-ion	1
	N. Fukunishi, T. Dantsuka, M. Fujimaki, T. Fujinawa, H. Hasebe, Y. Higurashi, E. Ikezawa, H. Imao, T. Kageyama, O. Kamigaito, M. Kase, M. Kidera, M. Komiyama, H. Kuboki, K. Kumagai, T. Maie, M. Nagase, T. Nakagawa, M. Nakamura, J. Ohnishi, H. Okuno, K. Ozeki, N. Sakamoto, K. Suda, A. Uchiyama, T. Watanabe, Y. Watanabe, K. Yamada, H. Yamasawa RIKEN Nishina Center, Wako, Japan
	The RIBF cascaded-cyclotrons have obtained, as of December 2012, uranium ion beams with an intensity of as high as 15 pnA (1 kW of power). This was achieved owing to deployment of a 28 GHz ECRIS, a new injector linac, a gas stripper and a bending-power upgrade of RIKEN fixed-frequency Ring Cyclotron as well as improvement of transmission efficiencies through cyclotrons and stability, etc.
	Slides MO1PB01 [12.793 MB]

MO1PB02	New Developments and Capabilities at the Coupled Cyclotron Facility at Michigan State University	ion, cyclotron, cryomodule, rfq	7
	A. Stolz, G. Bollen, A. Lapierre, D. Leitner, D.J. Morrissey, S. Schwarz, C. Sumithrarachchi, W. Wittmer NSCL, East Lansing, Michigan, USA
	A brief overview of the Coupled Cyclotron Facility will be presented with a focus on the newly commissioned stopped beam and reaccelerated radioactive ion beam capabilities. Commissioning results and operations experience of the combined system of Coupled Cyclotron Facility, A1900 fragment separator, gas stopper, EBIT charge-breeder and ReA linac will be presented.
	Slides MO1PB02 [42.670 MB]

MO2PB01	What We Learned from EMMA	lattice, resonance, injection, synchrotron	14
	S. Machida STFC/RAL/ASTeC, Chilton, Didcot, Oxon, United Kingdom
	Since the demonstration of acceleration in 2011, the study of EMMA aims for more detailed and quantitative understanding of a linear non-scaling FFAG. The talk will summarise the beam study for the last couple of years which includes effects of resonance crossing, a novel idea of COD correction, etc.
	Slides MO2PB01 [8.447 MB]

MOPPT018	End-to-End 6-D Tracking Using EMMA On-Line Model	injection, kicker, septum, extraction	70
	F. Méot BNL, Upton, Long Island, New York, USA D.J. Kelliher, S. Machida STFC/RAL/ASTeC, Chilton, Didcot, Oxon, United Kingdom B.J.A. Shepherd STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
	Numerical simulation of 6-dimensional, end-to-end beam transport in the prototype EMMA linear FFAG is presented and discussed. The simulation uses the 3-D OPERA field maps of the 42 cells, including the specific injection and extraction cells. It starts from upstream of the injection septum, and ends downstream of the extraction septum after 10-turn "serpentine" acceleration from 10 to 20 MeV. It includes the time function of the septa and injection and extraction pairs of kickers, and possible stray fields.

MOPPT019	A Compact, GeV, High-Intensity (CW) Racetrack FFAG	cyclotron, focusing, extraction, synchrotron	73
	C. Johnstone Fermilab, Batavia, Illinois, USA M. Berz, K. Makino MSU, East Lansing, Michigan, USA P. Snopok Illinois Institute of Technology, Chicago, Illinois, USA
	High-intensity and energy compact proton accelerators, especially those requiring milliamp currents, imply both CW operation and high acceleration gradients to mitigate losses. Above a few hundred MeV, losses must be under a per cent to avoid massive shielding and unmanageable activation. As relativistic energies are approached, the orbit separation on consecutive acceleration turns decreases for isochronous performance and to achieve higher acceleration gradients and orbit separation, RF modules must be employed rather than Dees, resulting in the larger separated-sector cyclotron footprint. However, the addition of strong focusing – with reversed gradients to capture both transverse planes – to conventional cyclotron fields promote inclusion of long synchrotron-like straight sections and implementation of high-gradient RF, even SCRF. The nsFFAG design has evolved into a a recirculating linear accelerator form with FFAG arcs. An ultra-compact, 0.2 – 1 GeV RLA FFAG design will be discussed (with a 3m x 5-6m footprint) that uses SC RF cryomodules achieving complete orbit separation at extraction and CW operation.

MOPPT025	Optimum Serpentine Acceleration in Scaling FFAG	linac, lattice, extraction, radio-frequency	85
	S.R. Koscielniak TRIUMF, Canada's National Laboratory for Particle and Nuclear Physics, Vancouver, Canada
	Serpentine acceleration is typified by fixed radio frequency, fixed magnetic field and a near (but not) isochronous lattice, radial motion of the orbit, and two or more reversals of the motion in RF phase. This was discovered in 2003 for linear non-scaling FFAGs in the relativistic regime. In 2013, Kyoto University School of Engineering pointed out that serpentine acceleration is possible also in scaling FFAGs and may span the non-relativistic to relativistic regime. As a function of two key parameters, field index and synchronous energy, this paper shows how to optimize the extraction energy and the voltage per turn for the scaling case. Optimization is difficult, and typically leads to poor performance: either extreme voltage or small acceleration range. Nevertheless, designs with credible acceleration parameters can be obtained; and indicative examples are presented herein.

MO3PB04	Comparison of Superconducting 230 MeV/u Synchro- and Isochronous Cyclotron Designs for Therapy with Cyclinacs	cyclotron, injection, linac, ion	108
	A. Garonna CERN, Geneva, Switzerland U. Amaldi, A. Laisné TERA, Novara, Italy L. Calabretta, D. Campo INFN/LNS, Catania, Italy
	Funding: This work was funded by the TERA Foundation (Novara, Italy). This work presents new superconducting compact cyclotron designs for injection in CABOTO, a linac developed by the TERA Foundation delivering C⁶⁺/H²⁺ beams up to 400 MeV/u for ion beam therapy. Two designs are compared in an industrial perspective under the same design constraints and methods: a synchrocyclotron and an isochronous cyclotron, both at the highest possible magnetic field and with an output energy of 230 MeV/u. This energy allows us to use the cyclotron as a stand-alone accelerator for proton therapy. The synchrocyclotron design features a central magnetic field of 5 T and an axisymmetric pole and a constant field index. The beam is injected axially with a spiral inflector. Resonant extraction allows beam ejection with moderate beam losses. The RF system operates in first harmonic (180° Dee), with modulation provided by a large rotating capacitor. The isochronous cyclotron design features a 3.2 T central magnetic field, four sectors and elliptical pole gaps in the hills and in the valleys. Spiraling is minimized and beam ejection is achieved with a single electrostatic deflector placed inside an empty valley. The two RF cavities operate in fourth harmonic.
	Slides MO3PB04 [4.314 MB]

MO4PB01	Experimental Study Towards High Beam Power FFAG	injection, space-charge, linac, cavity	111
	T. Uesugi Kyoto University, Research Reactor Institute, Osaka, Japan
	The FFAG complex at KURRI is not only the first proton FFAG accelerator facility for beam users but the one aiming to have high beam power. The talk will present various efforts to increase beam power for the last few years and systematic strategy in near future toward the space charge limit.
	Slides MO4PB01 [6.691 MB]

MO4PB03	Advanced FFAG Optics, Design and Experiment	emittance, 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]

TUPPT023	Design and Simulation of Cavity for 10 MeV Compact Cyclotron	cavity, cyclotron, coupling, simulation	200
	V. Afzalan, H. Afarideh, R. Azizi AUT, Tehran, Iran J.-S. Chai, M. Ghergherehchi SKKU, Suwon, Republic of Korea
	RF system is known as one of the most vital parts to produce the efficient accelerator system. In this paper, the RF system and cavity of 10 MeV AVF ( Azimuthally Varying Field ) Cyclotron for radioisotope production are designed. The Cyclotron works on 4th harmonic with Dee's voltage of 50 KV. In order to supply the expected accelerating voltages RF power coupling and RF tuner has been considered. The RF system is simulated using commercially available simulator, CST Microwave Studio code. In contrast the geometry of cavity is optimized to achieve suitable Q value in desired frequency. Since the factors are non-ideal during the fabrication process, the actual Q value of cavities is estimated.

TU3PB03	R&D of Helium Gas Stripper for Intense Uranium Beams	ion, target, electron, cyclotron	265
	H. Imao, T. Dantsuka, M. Fujimaki, N. Fukunishi, H. Hasebe, O. Kamigaito, M. Kase, H. Kuboki, K. Kumagai, T. Maie, H. Okuno, T. Watanabe, Y. Watanabe, K. Yamada, Y. Yano RIKEN Nishina Center, Wako, Japan
	Intensity upgrade of uranium beams is one of the main concerns at the RIKEN Radioactive Isotope Beam Factory (RIBF). The lifetime problem of carbon-foil strippers due to the high energy loss of uranium beams around 10~MeV/u was a principal bottleneck for the intensity upgrade in the acceleration scheme at the RIBF. We have developed a re-circulating He-gas stripper as an alternative to carbon foils for the acceleration of high-power uranium beams. The new stripping system was actually operated in user runs with U³⁵⁺ beams of more than 1 puA. Electron-stripped U⁶⁴⁺ beams were stably delivered to subsequent accelerators without serious deterioration of the system for six weeks. The new He-gas stripper, which removed the primary bottleneck in the high-intensity uranium acceleration, greatly contributed the tenfold increase of the average output intensity of the uranium beams from the previous year.
	Slides TU3PB03 [11.983 MB]

WEPPT011	Measurement of Radial Oscillation and Phase of Accelerating Beam in Kolkata Superconducting Cyclotron	cyclotron, extraction, resonance, betatron	344
	J. Pradhan, A. Agarwal, U. Bhunia, A. Chakrabarti, J. Debnath, M.K. Dey, A. Dutta, Z.A. Naser, S. Paul, V. Singh VECC, Kolkata, India
	This paper describes various measurements performed on the beam behavior with the help of the main probe and the differential probe to have a clear insight of the accelerating beam and the difficulties of beam -extraction process in the K500 superconducting cyclotron at Kolkata. Beam shadow measurements with three probes at three sectors were done to get the information of beam-centering and radial oscillations. The radial oscillation amplitude is estimated from the measurements. A differential probe was used to measure the turn separation and its modulation due to radial oscillation. With the help of magnetic field detuning method, the beam phase history was also measured.

WEPPT014	Analysis of Phase Bunching in the Central Region of the JAEA AVF Cyclotron	bunching, cyclotron, simulation, ion	350
	N. Miyawaki, H. Kashiwagi, S. Kurashima, S. Okumura JAEA/TARRI, Gunma-ken, Japan M. Fukuda RCNP, Osaka, Japan
	Phase bunching generated in the central region of an AVF cyclotron was estimated by a simplified geometric trajectory analysis model for particles traveling from the first to the second acceleration gap. In principle, a rising slope of a dee-voltage at the first acceleration gap is more or less effective for production of the phase bunching. The phase difference between particles at the second acceleration gap depends on combination of four parameters: the acceleration harmonic number (h), a span angle of the dee electrode, a span angle from the first to the second acceleration gap, a ratio between a peak dee-voltage and an extraction voltage of an ion source. In the case of the JAEA AVF cyclotron, the effective phase bunching was realized for h = 2 and 3, and the geometric condition of phase bunching was unrealistic for h = 1. An orbit simulation for the JAEA AVF cyclotron indicated that the initial beam phase width of 40 RF degrees for h = 2 was compressed to 11 RF degrees. The phase bunching evaluation based on the simplified geometric trajectory analysis was consistent with the orbit simulation result, and practical phase bunching was verified by beam phase width measurement.

WEPPT015	Study of Beam Capture in Compact Synchrocyclotron	synchrotron, synchro-cyclotron, injection, cyclotron	353
	S.A. Kostromin, G.A. Karamysheva, N.A. Morozov, E. Samsonov JINR, Dubna, Moscow Region, Russia
	Capture efficiency and main aspects of the beam dynamics during first turns and in a period of one synchrotron oscillation were studied in synchrocyclotron with driving magnetic field of ~5 Tesla. Corresponding simulations of the beam motion were done by means of numerical integration of the full equations of motion in the electro-magnetic field of accelerator. Main physical parameters for input data were taken similar to them for IBA S2C2.

WEPPT017	Beam Tracking Simulation for a 9 MeV Cyclotron	cyclotron, extraction, ion, ion-source	356
	S.Y. Jung, J.-S. Chai, J.-S. Chai, H.W. Kim, S.H. Kim, Y.S. Lee, H.S. Song, Y.H. Yeon SKKU, Suwon, Republic of Korea
	Following the adoption of internal PIG ion source making cyclotron more compact, the delicate beam trajectory simulation is required. In this paper, the optimization of initial condition of H-beam for the stable and well-controlled beam until the extraction region is reported. To accommodate the beam, the electromagnetic field distribution was analyzed by OPERA-3D and its phase error was verified with CYCLONE v8.4. In each iterative design, the beam trajectory was calculated by own developed numerical code to estimate its performance. The beam characteristics including the beam orbit, centering, energy gain and RF acceptance for vertical and horizontal directions were evaluated.

WEPPT018	Behavior of Space Charge Dominated Beam Envelope in Central Region of High Current Cyclotron	space-charge, simulation, injection, cyclotron	359
	R. Azizi, H. Afarideh, V. Afzalan AUT, Tehran, Iran J.-S. Chai, M. Ghergherehchi SKKU, Suwon, Republic of Korea
	In this paper the space charge effect in the two first turn after injection has been investigated. In order to determine beam envelopes, two corresponding equations were chosen. In addition, all steps of calculation were done by MATLAB program. It should be mentioned limiting current and also magnetic, electrical field and edge effect has been considered. As far as, the high current cyclotron with 0.8π mm mrad emittance has been studied and current alters till 10 mA.* *M. Reiser, Theory and Design of Charged Particle Beams (Wiley, New York, 1994), Chapters.3 and 4.

WEPPT029	The Cyclotron Complex for the DAEδALUS Experiment	cyclotron, injection, extraction, simulation	381
	A. Calanna, D. Campo, J.M. Conrad MIT, Cambridge, Massachusetts, USA L. Calabretta INFN/LNS, Catania, Italy M. Haj Tahar, F. Méot BNL, Upton, Long Island, New York, USA
	The cyclotron complex for the DAEδALUS CP-Violation neutrino experiment consists of a compact cyclotron able to accelerate high-current (5 electrical milliamp) H²⁺ beams up to an energy of 60 MeV/amu, cleanly extract this beam with a conventional septum arrangement, and transport it to a superconducting ring cyclotron able to accelerate the beam up to 800 MeV/amu. H²⁺ is dissociated with thin stripping foils for efficient extraction as protons for transport to a megawatt-class target for neutrino production. The injection cyclotron will be similar to the one proposed for the IsoDAR experiment (Paper WEPPT029). The Ring cyclotron is similar in size and engineering concept to the SRC at RIKEN. Space-charge dominated beam dynamics simulations using OPAL have been performed for an 8-sector geometry, and indicate acceptable transmission and low beam losses. Subsequent engineering magnet-design studies of Minervini et al. point to a 6-sector configuration as more practical. Recalculation of the beam dynamics for this new configuration will be performed in the coming year. Results of the studies conducted to date will be presented.

WE4PB01	Tracking in a Cyclotron with Geant4	TRIUMF, cyclotron, simulation, proton	423
	F.W. Jones, T. Planche, Y.-N. Rao TRIUMF, Canada's National Laboratory for Particle and Nuclear Physics, Vancouver, Canada
	Building on its precursor GEANT, the tracking and simulation toolkit Geant4 has been conceived and realised in a very general fashion, with much attention given to the modeling of electric and magnetic fields and the accuracy of tracking charged particles through them. As evidenced by the G4Beamline application, Geant4 offers a unique simulation approach to beam lines and accelerators, in a 3D geometry and without some of the limitations posed by conventional optics and tracking codes. Here we apply G4Beamline to the TRIUMF cyclotron, describing the generation and input of the field data, accuracy of closed orbits, stability of multi-turn tracking, tracking accelerated orbits, and phase acceptance. Geant4's 3D visualization tools allow detailed examination of trajectories as well as a particle's-eye view of the acceleration process.
	Slides WE4PB01 [4.146 MB]

TH1PB02	Tuning of the PSI 590 MeV Ring Cyclotron for Accepting and Accelerating a Rebunched 72 MeV Proton Beam	cyclotron, injection, proton, extraction	437
	J.M. Humbel, C. Baumgarten, J. Grillenberger, W. Joho, H. Muller, H. Zhang PSI, Villigen PSI, Switzerland
	In the past year the production of a 1.42 MW proton beam at a relative loss level of 10^-4 at PSI’s proton facility became routine operation. In addition, the inaugurated buncher based beam injection into the 590 MeV Ringcyclotron made a remarkable step forward. In particular, an almost dispersion free setting of the beamline region around the 500 MHz rebuncher in the 72 MeV transfer line has been established and a perfect matching of the dispersion into the Ringcyclotron has been achieved. This buncher-operation optimized facility setting could be advanced up to the ordinary stable standard 2.2 mA production proton beam. With the buncher voltage turned on, at the moment the beam extracted from the Ringcyclotron is limited to below 1 mA due to raising losses, mainly generated by space charge induced distortions of the beam bunches. For a better understanding of these effects a substantial effort in modelling of the accelerated beam is under way. In particular, the influence of the trim coil fields is being implemented into the OPAL simulation code and the insertion of an additional time structure measurement probe in the Ringcyclotron is proposed.
	Slides TH1PB02 [9.281 MB]

FR1PB01	Operation Mode of AIC-144 Multipurpose Isochronous Cyclotron for Eye Melanoma Treatment	cyclotron, extraction, proton, vacuum	461
	G.A. Karamysheva, I. Amirkhanov, I.N. Kiyan, N.A. Morozov, E. Samsonov JINR, Dubna, Moscow Region, Russia K. Daniel, K. Gugula, J. Sulikowski IFJ-PAN, Kraków, Poland
	Computational and experimental results concerning acceleration and extraction of the 60-MeV proton beam at AIC-144 cyclotron of the Institute of Nuclear Physics (Kraków, Poland) are considered. A proton beam of the AIC-144 cyclotron is accelerated without large losses in the radial region of 12-62 cm and is extracted from the cyclotron with a pretty good overall efficiency of ~35%. The beam was used for successful treatment of 15 patients in 2011-2012.
	Slides FR1PB01 [3.828 MB]

FR1PB04	GANIL Operation Status and Upgrade of SPIRAL1	ion, ion-source, target, cyclotron	470
	O. Kamalou, O. Bajeat, F. Chautard, P. Delahaye, M. Dubois, P. Jardin, L. Maunoury GANIL, Caen, France
	The GANIL facility (Grand Accélérateur National d’Ions Lourds) at Caen produces and accelerates stable ion beams since 1982 for nuclear physics, atomic physics, radiobiology and material irradiation. Nowadays, an intense exotic beam is produced by the Isotope Separation On-Line method at the SPIRAL1 facility. It is running since 2001, producing and post-accelerating radioactive ion beams of noble gas type mainly. The review of the operation from 2001 to 2013 is presented. Due to a large request of physicists, the facility will be enhanced within the frame of the project Upgrade SPIRAL1. The goal of the project is to broaden the range of post-accelerated exotic beams available especially to all the condensable light elements as P, Mg, Al, Cl etc The upgrade of SPIRAL1 is in progress and the new beams would be delivered for operation by the end of 2015.
	Slides FR1PB04 [1.514 MB]

Paper

Title

Other Keywords

Page

MO1PB01

Acceleration of Intense Heavy Ion Beams in RIBF Cascaded-Cyclotrons

ion, cyclotron, extraction, heavy-ion

1

N. Fukunishi, T. Dantsuka, M. Fujimaki, T. Fujinawa, H. Hasebe, Y. Higurashi, E. Ikezawa, H. Imao, T. Kageyama, O. Kamigaito, M. Kase, M. Kidera, M. Komiyama, H. Kuboki, K. Kumagai, T. Maie, M. Nagase, T. Nakagawa, M. Nakamura, J. Ohnishi, H. Okuno, K. Ozeki, N. Sakamoto, K. Suda, A. Uchiyama, T. Watanabe, Y. Watanabe, K. Yamada, H. Yamasawa
RIKEN Nishina Center, Wako, Japan

The RIBF cascaded-cyclotrons have obtained, as of December 2012, uranium ion beams with an intensity of as high as 15 pnA (1 kW of power). This was achieved owing to deployment of a 28 GHz ECRIS, a new injector linac, a gas stripper and a bending-power upgrade of RIKEN fixed-frequency Ring Cyclotron as well as improvement of transmission efficiencies through cyclotrons and stability, etc.

Slides MO1PB01 [12.793 MB]

MO1PB02

New Developments and Capabilities at the Coupled Cyclotron Facility at Michigan State University

ion, cyclotron, cryomodule, rfq

7

A. Stolz, G. Bollen, A. Lapierre, D. Leitner, D.J. Morrissey, S. Schwarz, C. Sumithrarachchi, W. Wittmer
NSCL, East Lansing, Michigan, USA

A brief overview of the Coupled Cyclotron Facility will be presented with a focus on the newly commissioned stopped beam and reaccelerated radioactive ion beam capabilities. Commissioning results and operations experience of the combined system of Coupled Cyclotron Facility, A1900 fragment separator, gas stopper, EBIT charge-breeder and ReA linac will be presented.

Slides MO1PB02 [42.670 MB]

MO2PB01

What We Learned from EMMA

lattice, resonance, injection, synchrotron

14

S. Machida
STFC/RAL/ASTeC, Chilton, Didcot, Oxon, United Kingdom

Since the demonstration of acceleration in 2011, the study of EMMA aims for more detailed and quantitative understanding of a linear non-scaling FFAG. The talk will summarise the beam study for the last couple of years which includes effects of resonance crossing, a novel idea of COD correction, etc.

Slides MO2PB01 [8.447 MB]

MOPPT018

End-to-End 6-D Tracking Using EMMA On-Line Model

injection, kicker, septum, extraction

70

F. Méot
BNL, Upton, Long Island, New York, USA
D.J. Kelliher, S. Machida
STFC/RAL/ASTeC, Chilton, Didcot, Oxon, United Kingdom
B.J.A. Shepherd
STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom

Numerical simulation of 6-dimensional, end-to-end beam transport in the prototype EMMA linear FFAG is presented and discussed. The simulation uses the 3-D OPERA field maps of the 42 cells, including the specific injection and extraction cells. It starts from upstream of the injection septum, and ends downstream of the extraction septum after 10-turn "serpentine" acceleration from 10 to 20 MeV. It includes the time function of the septa and injection and extraction pairs of kickers, and possible stray fields.

MOPPT019

A Compact, GeV, High-Intensity (CW) Racetrack FFAG

cyclotron, focusing, extraction, synchrotron

73

C. Johnstone
Fermilab, Batavia, Illinois, USA
M. Berz, K. Makino
MSU, East Lansing, Michigan, USA
P. Snopok
Illinois Institute of Technology, Chicago, Illinois, USA

High-intensity and energy compact proton accelerators, especially those requiring milliamp currents, imply both CW operation and high acceleration gradients to mitigate losses. Above a few hundred MeV, losses must be under a per cent to avoid massive shielding and unmanageable activation. As relativistic energies are approached, the orbit separation on consecutive acceleration turns decreases for isochronous performance and to achieve higher acceleration gradients and orbit separation, RF modules must be employed rather than Dees, resulting in the larger separated-sector cyclotron footprint. However, the addition of strong focusing – with reversed gradients to capture both transverse planes – to conventional cyclotron fields promote inclusion of long synchrotron-like straight sections and implementation of high-gradient RF, even SCRF. The nsFFAG design has evolved into a a recirculating linear accelerator form with FFAG arcs. An ultra-compact, 0.2 – 1 GeV RLA FFAG design will be discussed (with a 3m x 5-6m footprint) that uses SC RF cryomodules achieving complete orbit separation at extraction and CW operation.

MOPPT025

Optimum Serpentine Acceleration in Scaling FFAG

linac, lattice, extraction, radio-frequency

85

S.R. Koscielniak
TRIUMF, Canada's National Laboratory for Particle and Nuclear Physics, Vancouver, Canada

Serpentine acceleration is typified by fixed radio frequency, fixed magnetic field and a near (but not) isochronous lattice, radial motion of the orbit, and two or more reversals of the motion in RF phase. This was discovered in 2003 for linear non-scaling FFAGs in the relativistic regime. In 2013, Kyoto University School of Engineering pointed out that serpentine acceleration is possible also in scaling FFAGs and may span the non-relativistic to relativistic regime. As a function of two key parameters, field index and synchronous energy, this paper shows how to optimize the extraction energy and the voltage per turn for the scaling case. Optimization is difficult, and typically leads to poor performance: either extreme voltage or small acceleration range. Nevertheless, designs with credible acceleration parameters can be obtained; and indicative examples are presented herein.

MO3PB04

Comparison of Superconducting 230 MeV/u Synchro- and Isochronous Cyclotron Designs for Therapy with Cyclinacs

cyclotron, injection, linac, ion

108

A. Garonna
CERN, Geneva, Switzerland
U. Amaldi, A. Laisné
TERA, Novara, Italy
L. Calabretta, D. Campo
INFN/LNS, Catania, Italy

Funding: This work was funded by the TERA Foundation (Novara, Italy).
This work presents new superconducting compact cyclotron designs for injection in CABOTO, a linac developed by the TERA Foundation delivering C⁶⁺/H²⁺ beams up to 400 MeV/u for ion beam therapy. Two designs are compared in an industrial perspective under the same design constraints and methods: a synchrocyclotron and an isochronous cyclotron, both at the highest possible magnetic field and with an output energy of 230 MeV/u. This energy allows us to use the cyclotron as a stand-alone accelerator for proton therapy. The synchrocyclotron design features a central magnetic field of 5 T and an axisymmetric pole and a constant field index. The beam is injected axially with a spiral inflector. Resonant extraction allows beam ejection with moderate beam losses. The RF system operates in first harmonic (180° Dee), with modulation provided by a large rotating capacitor. The isochronous cyclotron design features a 3.2 T central magnetic field, four sectors and elliptical pole gaps in the hills and in the valleys. Spiraling is minimized and beam ejection is achieved with a single electrostatic deflector placed inside an empty valley. The two RF cavities operate in fourth harmonic.

Slides MO3PB04 [4.314 MB]

MO4PB01

Experimental Study Towards High Beam Power FFAG

injection, space-charge, linac, cavity

111

T. Uesugi
Kyoto University, Research Reactor Institute, Osaka, Japan

The FFAG complex at KURRI is not only the first proton FFAG accelerator facility for beam users but the one aiming to have high beam power. The talk will present various efforts to increase beam power for the last few years and systematic strategy in near future toward the space charge limit.

Slides MO4PB01 [6.691 MB]

MO4PB03

Advanced FFAG Optics, Design and Experiment

emittance, 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]

TUPPT023

Design and Simulation of Cavity for 10 MeV Compact Cyclotron

cavity, cyclotron, coupling, simulation

200

V. Afzalan, H. Afarideh, R. Azizi
AUT, Tehran, Iran
J.-S. Chai, M. Ghergherehchi
SKKU, Suwon, Republic of Korea

RF system is known as one of the most vital parts to produce the efficient accelerator system. In this paper, the RF system and cavity of 10 MeV AVF ( Azimuthally Varying Field ) Cyclotron for radioisotope production are designed. The Cyclotron works on 4th harmonic with Dee's voltage of 50 KV. In order to supply the expected accelerating voltages RF power coupling and RF tuner has been considered. The RF system is simulated using commercially available simulator, CST Microwave Studio code. In contrast the geometry of cavity is optimized to achieve suitable Q value in desired frequency. Since the factors are non-ideal during the fabrication process, the actual Q value of cavities is estimated.

TU3PB03

R&D of Helium Gas Stripper for Intense Uranium Beams

ion, target, electron, cyclotron

265

H. Imao, T. Dantsuka, M. Fujimaki, N. Fukunishi, H. Hasebe, O. Kamigaito, M. Kase, H. Kuboki, K. Kumagai, T. Maie, H. Okuno, T. Watanabe, Y. Watanabe, K. Yamada, Y. Yano
RIKEN Nishina Center, Wako, Japan

Intensity upgrade of uranium beams is one of the main concerns at the RIKEN Radioactive Isotope Beam Factory (RIBF). The lifetime problem of carbon-foil strippers due to the high energy loss of uranium beams around 10~MeV/u was a principal bottleneck for the intensity upgrade in the acceleration scheme at the RIBF. We have developed a re-circulating He-gas stripper as an alternative to carbon foils for the acceleration of high-power uranium beams. The new stripping system was actually operated in user runs with U³⁵⁺ beams of more than 1 puA. Electron-stripped U⁶⁴⁺ beams were stably delivered to subsequent accelerators without serious deterioration of the system for six weeks. The new He-gas stripper, which removed the primary bottleneck in the high-intensity uranium acceleration, greatly contributed the tenfold increase of the average output intensity of the uranium beams from the previous year.

Slides TU3PB03 [11.983 MB]

WEPPT011

Measurement of Radial Oscillation and Phase of Accelerating Beam in Kolkata Superconducting Cyclotron

cyclotron, extraction, resonance, betatron

344

J. Pradhan, A. Agarwal, U. Bhunia, A. Chakrabarti, J. Debnath, M.K. Dey, A. Dutta, Z.A. Naser, S. Paul, V. Singh
VECC, Kolkata, India

This paper describes various measurements performed on the beam behavior with the help of the main probe and the differential probe to have a clear insight of the accelerating beam and the difficulties of beam -extraction process in the K500 superconducting cyclotron at Kolkata. Beam shadow measurements with three probes at three sectors were done to get the information of beam-centering and radial oscillations. The radial oscillation amplitude is estimated from the measurements. A differential probe was used to measure the turn separation and its modulation due to radial oscillation. With the help of magnetic field detuning method, the beam phase history was also measured.

WEPPT014

Analysis of Phase Bunching in the Central Region of the JAEA AVF Cyclotron

bunching, cyclotron, simulation, ion

350

N. Miyawaki, H. Kashiwagi, S. Kurashima, S. Okumura
JAEA/TARRI, Gunma-ken, Japan
M. Fukuda
RCNP, Osaka, Japan

Phase bunching generated in the central region of an AVF cyclotron was estimated by a simplified geometric trajectory analysis model for particles traveling from the first to the second acceleration gap. In principle, a rising slope of a dee-voltage at the first acceleration gap is more or less effective for production of the phase bunching. The phase difference between particles at the second acceleration gap depends on combination of four parameters: the acceleration harmonic number (h), a span angle of the dee electrode, a span angle from the first to the second acceleration gap, a ratio between a peak dee-voltage and an extraction voltage of an ion source. In the case of the JAEA AVF cyclotron, the effective phase bunching was realized for h = 2 and 3, and the geometric condition of phase bunching was unrealistic for h = 1. An orbit simulation for the JAEA AVF cyclotron indicated that the initial beam phase width of 40 RF degrees for h = 2 was compressed to 11 RF degrees. The phase bunching evaluation based on the simplified geometric trajectory analysis was consistent with the orbit simulation result, and practical phase bunching was verified by beam phase width measurement.

WEPPT015

Study of Beam Capture in Compact Synchrocyclotron

synchrotron, synchro-cyclotron, injection, cyclotron

353

S.A. Kostromin, G.A. Karamysheva, N.A. Morozov, E. Samsonov
JINR, Dubna, Moscow Region, Russia

Capture efficiency and main aspects of the beam dynamics during first turns and in a period of one synchrotron oscillation were studied in synchrocyclotron with driving magnetic field of ~5 Tesla. Corresponding simulations of the beam motion were done by means of numerical integration of the full equations of motion in the electro-magnetic field of accelerator. Main physical parameters for input data were taken similar to them for IBA S2C2.

WEPPT017

Beam Tracking Simulation for a 9 MeV Cyclotron

cyclotron, extraction, ion, ion-source

356

S.Y. Jung, J.-S. Chai, J.-S. Chai, H.W. Kim, S.H. Kim, Y.S. Lee, H.S. Song, Y.H. Yeon
SKKU, Suwon, Republic of Korea

Following the adoption of internal PIG ion source making cyclotron more compact, the delicate beam trajectory simulation is required. In this paper, the optimization of initial condition of H-beam for the stable and well-controlled beam until the extraction region is reported. To accommodate the beam, the electromagnetic field distribution was analyzed by OPERA-3D and its phase error was verified with CYCLONE v8.4. In each iterative design, the beam trajectory was calculated by own developed numerical code to estimate its performance. The beam characteristics including the beam orbit, centering, energy gain and RF acceptance for vertical and horizontal directions were evaluated.

WEPPT018

Behavior of Space Charge Dominated Beam Envelope in Central Region of High Current Cyclotron

space-charge, simulation, injection, cyclotron

359

R. Azizi, H. Afarideh, V. Afzalan
AUT, Tehran, Iran
J.-S. Chai, M. Ghergherehchi
SKKU, Suwon, Republic of Korea

In this paper the space charge effect in the two first turn after injection has been investigated. In order to determine beam envelopes, two corresponding equations were chosen. In addition, all steps of calculation were done by MATLAB program. It should be mentioned limiting current and also magnetic, electrical field and edge effect has been considered. As far as, the high current cyclotron with 0.8π mm mrad emittance has been studied and current alters till 10 mA.*
*M. Reiser, Theory and Design of Charged Particle Beams (Wiley, New York, 1994), Chapters.3 and 4.

WEPPT029

The Cyclotron Complex for the DAEδALUS Experiment

cyclotron, injection, extraction, simulation

381

A. Calanna, D. Campo, J.M. Conrad
MIT, Cambridge, Massachusetts, USA
L. Calabretta
INFN/LNS, Catania, Italy
M. Haj Tahar, F. Méot
BNL, Upton, Long Island, New York, USA

The cyclotron complex for the DAEδALUS CP-Violation neutrino experiment consists of a compact cyclotron able to accelerate high-current (5 electrical milliamp) H²⁺ beams up to an energy of 60 MeV/amu, cleanly extract this beam with a conventional septum arrangement, and transport it to a superconducting ring cyclotron able to accelerate the beam up to 800 MeV/amu. H²⁺ is dissociated with thin stripping foils for efficient extraction as protons for transport to a megawatt-class target for neutrino production. The injection cyclotron will be similar to the one proposed for the IsoDAR experiment (Paper WEPPT029). The Ring cyclotron is similar in size and engineering concept to the SRC at RIKEN. Space-charge dominated beam dynamics simulations using OPAL have been performed for an 8-sector geometry, and indicate acceptable transmission and low beam losses. Subsequent engineering magnet-design studies of Minervini et al. point to a 6-sector configuration as more practical. Recalculation of the beam dynamics for this new configuration will be performed in the coming year. Results of the studies conducted to date will be presented.

WE4PB01

Tracking in a Cyclotron with Geant4

TRIUMF, cyclotron, simulation, proton

423

F.W. Jones, T. Planche, Y.-N. Rao
TRIUMF, Canada's National Laboratory for Particle and Nuclear Physics, Vancouver, Canada

Building on its precursor GEANT, the tracking and simulation toolkit Geant4 has been conceived and realised in a very general fashion, with much attention given to the modeling of electric and magnetic fields and the accuracy of tracking charged particles through them. As evidenced by the G4Beamline application, Geant4 offers a unique simulation approach to beam lines and accelerators, in a 3D geometry and without some of the limitations posed by conventional optics and tracking codes. Here we apply G4Beamline to the TRIUMF cyclotron, describing the generation and input of the field data, accuracy of closed orbits, stability of multi-turn tracking, tracking accelerated orbits, and phase acceptance. Geant4's 3D visualization tools allow detailed examination of trajectories as well as a particle's-eye view of the acceleration process.

Slides WE4PB01 [4.146 MB]

TH1PB02

Tuning of the PSI 590 MeV Ring Cyclotron for Accepting and Accelerating a Rebunched 72 MeV Proton Beam

cyclotron, injection, proton, extraction

437

J.M. Humbel, C. Baumgarten, J. Grillenberger, W. Joho, H. Muller, H. Zhang
PSI, Villigen PSI, Switzerland

In the past year the production of a 1.42 MW proton beam at a relative loss level of 10^-4 at PSI’s proton facility became routine operation. In addition, the inaugurated buncher based beam injection into the 590 MeV Ringcyclotron made a remarkable step forward. In particular, an almost dispersion free setting of the beamline region around the 500 MHz rebuncher in the 72 MeV transfer line has been established and a perfect matching of the dispersion into the Ringcyclotron has been achieved. This buncher-operation optimized facility setting could be advanced up to the ordinary stable standard 2.2 mA production proton beam. With the buncher voltage turned on, at the moment the beam extracted from the Ringcyclotron is limited to below 1 mA due to raising losses, mainly generated by space charge induced distortions of the beam bunches. For a better understanding of these effects a substantial effort in modelling of the accelerated beam is under way. In particular, the influence of the trim coil fields is being implemented into the OPAL simulation code and the insertion of an additional time structure measurement probe in the Ringcyclotron is proposed.

Slides TH1PB02 [9.281 MB]

FR1PB01

Operation Mode of AIC-144 Multipurpose Isochronous Cyclotron for Eye Melanoma Treatment

cyclotron, extraction, proton, vacuum

461

G.A. Karamysheva, I. Amirkhanov, I.N. Kiyan, N.A. Morozov, E. Samsonov
JINR, Dubna, Moscow Region, Russia
K. Daniel, K. Gugula, J. Sulikowski
IFJ-PAN, Kraków, Poland

Computational and experimental results concerning acceleration and extraction of the 60-MeV proton beam at AIC-144 cyclotron of the Institute of Nuclear Physics (Kraków, Poland) are considered. A proton beam of the AIC-144 cyclotron is accelerated without large losses in the radial region of 12-62 cm and is extracted from the cyclotron with a pretty good overall efficiency of ~35%. The beam was used for successful treatment of 15 patients in 2011-2012.

Slides FR1PB01 [3.828 MB]

FR1PB04

GANIL Operation Status and Upgrade of SPIRAL1

ion, ion-source, target, cyclotron

470

O. Kamalou, O. Bajeat, F. Chautard, P. Delahaye, M. Dubois, P. Jardin, L. Maunoury
GANIL, Caen, France

The GANIL facility (Grand Accélérateur National d’Ions Lourds) at Caen produces and accelerates stable ion beams since 1982 for nuclear physics, atomic physics, radiobiology and material irradiation. Nowadays, an intense exotic beam is produced by the Isotope Separation On-Line method at the SPIRAL1 facility. It is running since 2001, producing and post-accelerating radioactive ion beams of noble gas type mainly. The review of the operation from 2001 to 2013 is presented. Due to a large request of physicists, the facility will be enhanced within the frame of the project Upgrade SPIRAL1. The goal of the project is to broaden the range of post-accelerated exotic beams available especially to all the condensable light elements as P, Mg, Al, Cl etc The upgrade of SPIRAL1 is in progress and the new beams would be delivered for operation by the end of 2015.

Slides FR1PB04 [1.514 MB]