Cyclotrons2013 - List of Keywords (resonance)

Paper	Title	Other Keywords	Page
MO1PB03	Current Status of the Superconducting Cyclotron Project at Kolkata	cyclotron, extraction, target, diagnostics	11
	J. Debnath, A. Chakrabarti, M.K. Dey VECC, Kolkata, India
	The commissioning of Kolkata superconducting cyclotron with internal ion beam had been reported in the last cyclotron conference. At that time, there was gradual beam loss due to poor vacuum. After installing a higher capacity liquid helium plant the cryo-panels were made functional leading to a substantial increase in the beam intensity. It was hoped that higher beam intensity would help in extraction of a measurable fraction of the beam, but that did not happen. Detailed investigation of beam behavior with the help of three beam probes, installed temporarily at three sectors, revealed that the beam goes highly off-centered while passing through the resonance zone. A plastic scintillator based phase probe was mounted on the radial probe and beam phase was measured accurately. It was quite clear that large amount of field imperfection was prohibiting the beam to be extracted. So magnetic field measurement has been started again and considerable amount of harmonic and average field errors have been found. In this paper we report the important developments since 2010.
	Slides MO1PB03 [13.028 MB]

MO2PB01	What We Learned from EMMA	acceleration, lattice, 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]

MO3PB02	Design Study of a Superconducting AVF Cyclotron for Proton Therapy	cyclotron, extraction, proton, cavity	102
	H. Tsutsui, A. Hashimoto, Y. Mikami, H. Mitsubori, T. Mitsumoto, Y. Touchi, T. Ueda, K. Uno, K. Watazawa, S. Yajima, J.Y. Yoshida, K.U. Yumoto SHI, Tokyo, Japan
	Since a cyclotron has better beam quality than that of a synchrocyclotron, we have designed a 4 Tesla superconducting AVF cyclotron for proton therapy. Its weight is less than 60 tons, which is about one fourth of our normal conducting 230 MeV cyclotron. In order to reduce the size and the weight without deteriorating the beam stability, the hill gap around the outer pole radius is made small. Calculated extraction efficiency is higher than 60%, by arranging the extraction elements properly. The low temperature superconducting coil using NbTi wire is conduction-cooled by 4K GM cryocooler. Three dimensional electromagnetic finite element codes have been used during all phases of basic design.
	Slides MO3PB02 [13.506 MB]

TUPPT011	Measurement of Turn Structure in the Central Region of TRIUMF Cyclotron	cyclotron, TRIUMF, feedback, extraction	177
	T. Planche, R.A. Baartman, Y.-N. Rao TRIUMF, Canada's National Laboratory for Particle and Nuclear Physics, Vancouver, Canada
	To get the most out of the existing beam diagnostics in the TRIUMF cyclotron, we started in 2011 to developed new data processing and visualization tools. The main advantage of these Matlab-based tools, compared to old VMS-based tools, is that they can benefit from a much larger library of modern data processing and visualization algorithms. This effort has already shown itself very useful to highlight essential features of the beam dynamics which remained unnoticed before. In this paper we present measurements results displaying beam dynamics process, and in particular space charge related process, happening in the central region of the TRIUMF cyclotron.
	Poster TUPPT011 [32.212 MB]

TUPSH003	Conceptual Design of a 100 MeV Injector Cyclotron	cyclotron, proton, cavity, extraction	224
	M. Li, J.J. Yang, T.J. Zhang, J.Q. Zhong CIAE, Beijing, People's Republic of China
	Accelerator driven system (ADS) is advanced clean nuclear energy system based on a high power accelerator, which has been proposed worldwide in recent years. Referring to the experiences from the existing PSI high power proton facility, an 800 MeV cyclotron is under design at CIAE (China Institute of Atomic Energy) as a candidate of high power proton driver. Given the extremely high beam power to be extracted, a tiny beam loss can lead to disastrous result for the cyclotron. Especially, the beam loss during extraction is the critical issue with respect to the feasibility and reliability of the design, which needs to be investigated in great detail from the very beginning. In this paper, the extraction scheme and beamline elements design are presented, and the detailed beam loss distribution during extraction will be calculated by numerical simulation with the large-scale parallel code OPAL-CYCL.

TUPSH008	Conceptual Design of the 100 MeV Separated Sector Cyclotron	cyclotron, simulation, extraction, magnet-design	236
	B. Mahdian, H. Afarideh, R. Solhju AUT, Tehran, Iran J.-S. Chai, M. Ghergherehchi SKKU, Suwon, Republic of Korea
	The 100 MeV separated sector cyclotron was designed at Amirkabir University of Technology (AUT), which was aimed for various applications including radioactive ion-beam (RIB) production and proton therapy. It has four separated sector magnets. The cyclotron magnet design was based on an iterative process starting from a simple model that requires the vision of the complete cyclotron and the possibility of integration of all subsystems. By computer simulation with the 3D (CST) and 2D (POSSION) codes, principle parameters of the cyclotron magnet system were estimated (pole radius 180 cm, outer diameter 640 cm, height 300 cm). The results showed that the isochronous deviations between simulated values and the calculation one are smaller than 5 Gauss at most radii and therefore fulfilled the requirements. This work has been done with high accuracy which is proved by particle trajectories and considered mesh range. It has been concluded that it can be possible to design and develop this high energy cyclotron by introducing simple model without using trim and harmonic coils.

TU4PB01	Mapping of the New IBA Superconducting Synchrocyclotron (S2C2) for Proton Therapy	proton, extraction, synchro-cyclotron, cyclotron	272
	J. van de Walle, W.J.G.M. Kleeven, C. L'Abbate, V. Nuttens, Y. Paradis IBA, Louvain-la-Neuve, Belgium M. Conjat, J. Mandrillon, P. Mandrillon AIMA, Nice, France
	The magnetic field in the Superconducting Synchrocyclotron (S2C2) has been measured with a newly developed mapping system during the commissioning of the machine at IBA. The major difference with other mapping systems at IBA is the usage of a search coil, which provides high linearity over a large magnetic field range and the possibility to measure in a more time economic way. The first mapping results of the S2C2 were compared with OPERA3D calculations. The average field, the tune functions and the first harmonic were the main quantities which were compared and showed good agreement with the model. For example, the average field was within 0.3% of the calculation over the entire machine. In order to assess the efficiency of the regenerative extraction mechanism, protons were tracked in the measured map up to extraction. The horizontal position of the main coil was found to be a crucial parameter for the optimization of the extraction. A dedicated linear mapping system consisting of 7 Hall probes was positioned in the extraction channel of the S2C2. The field values from this linear mapping system were used to assess the optics of the beam exiting the S2C2.
	Slides TU4PB01 [2.357 MB]

WE1PB01	The Houghton College Cyclotron: a Tool for Educating Undergraduates	cyclotron, target, vacuum, ion	286
	M.E. Yuly Houghton College, Houghton, New York, USA
	The cyclotron is an ideal undergraduate research project because its operation and use involve so many of the principles covered in the undergraduate physics curriculum – from resonant circuits to nuclear reactions. The physics program at Houghton College, as part of an emphasis on active learning, requires all majors to complete a multiyear research project culminating in an undergraduate thesis. Over the past ten years seven students have constructed a working 1.2 T tabletop cyclotron theoretically capable of producing approximately 400 keV protons. The construction and performance of the cyclotron will be discussed, as well as its use as an educational tool.
	Slides WE1PB01 [28.909 MB]

WEPPT011	Measurement of Radial Oscillation and Phase of Accelerating Beam in Kolkata Superconducting Cyclotron	cyclotron, extraction, acceleration, 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.

WEPPT012	Beam Dynamics in Presence of Imperfection Fields Near the Extraction Zone of Kolkata Superconducting Cyclotron	extraction, cyclotron, simulation, betatron	347
	J. Debnath, U. Bhunia, A. Chakrabarti, M.K. Dey, A. Dutta, Z.A. Naser, S. Paul, J. Pradhan, V. Singh VECC, Kolkata, India
	Funding: VECC, DAE The superconducting cyclotron at Kolkata has accelerated the ion beams up to the extraction radius producing neutrons via nuclear reactions. After that the beam extraction process has been tried exhaustively. But rigorous beam extraction trials indicate towards some kind of error field, which was not possible to balance with the trim coil operated in harmonic-coil mode. It is found that the beam is being off-centered by a large amount after crossing the resonance zone and it is not reaching the extraction radius in proper path. This paper will be emphasizing the effect of various kind of error field on the beam. However, the magnetic field is being measured again to know the exact distribution of the field.

WEPPT025	Beam Physics Demonstrations with the Rutgers 12-Inch Cyclotron	cyclotron, ion, betatron, focusing	369
	T.W. Koeth UMD, College Park, Maryland, USA
	The Rutgers 12-Inch Cyclotron is a research grade accelerator dedicated to undergraduate education.[1] From its inception, it has been intended for instruction and has been designed to demonstrate classic beam physics phenomena. The machine is easily reconfigured, allowing experiments to be designed and performed within one academic semester. Our cyclotron gives students a hands-on opportunity to operate an accelerator and directly observe many fundamental beam physics concepts, including axial and radial betatron motion, destructive resonances, weak and azimuthally varying field (AVF) focusing schemes, DEE voltage effects, and more.

WE3PB01	Experimental Study of Resonance Crossing with a Paul Trap	emittance, 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

MO1PB03

Current Status of the Superconducting Cyclotron Project at Kolkata

cyclotron, extraction, target, diagnostics

11

J. Debnath, A. Chakrabarti, M.K. Dey
VECC, Kolkata, India

The commissioning of Kolkata superconducting cyclotron with internal ion beam had been reported in the last cyclotron conference. At that time, there was gradual beam loss due to poor vacuum. After installing a higher capacity liquid helium plant the cryo-panels were made functional leading to a substantial increase in the beam intensity. It was hoped that higher beam intensity would help in extraction of a measurable fraction of the beam, but that did not happen. Detailed investigation of beam behavior with the help of three beam probes, installed temporarily at three sectors, revealed that the beam goes highly off-centered while passing through the resonance zone. A plastic scintillator based phase probe was mounted on the radial probe and beam phase was measured accurately. It was quite clear that large amount of field imperfection was prohibiting the beam to be extracted. So magnetic field measurement has been started again and considerable amount of harmonic and average field errors have been found. In this paper we report the important developments since 2010.

Slides MO1PB03 [13.028 MB]

MO2PB01

What We Learned from EMMA

acceleration, lattice, 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]

MO3PB02

Design Study of a Superconducting AVF Cyclotron for Proton Therapy

cyclotron, extraction, proton, cavity

102

H. Tsutsui, A. Hashimoto, Y. Mikami, H. Mitsubori, T. Mitsumoto, Y. Touchi, T. Ueda, K. Uno, K. Watazawa, S. Yajima, J.Y. Yoshida, K.U. Yumoto
SHI, Tokyo, Japan

Since a cyclotron has better beam quality than that of a synchrocyclotron, we have designed a 4 Tesla superconducting AVF cyclotron for proton therapy. Its weight is less than 60 tons, which is about one fourth of our normal conducting 230 MeV cyclotron. In order to reduce the size and the weight without deteriorating the beam stability, the hill gap around the outer pole radius is made small. Calculated extraction efficiency is higher than 60%, by arranging the extraction elements properly. The low temperature superconducting coil using NbTi wire is conduction-cooled by 4K GM cryocooler. Three dimensional electromagnetic finite element codes have been used during all phases of basic design.

Slides MO3PB02 [13.506 MB]

TUPPT011

Measurement of Turn Structure in the Central Region of TRIUMF Cyclotron

cyclotron, TRIUMF, feedback, extraction

177

T. Planche, R.A. Baartman, Y.-N. Rao
TRIUMF, Canada's National Laboratory for Particle and Nuclear Physics, Vancouver, Canada

To get the most out of the existing beam diagnostics in the TRIUMF cyclotron, we started in 2011 to developed new data processing and visualization tools. The main advantage of these Matlab-based tools, compared to old VMS-based tools, is that they can benefit from a much larger library of modern data processing and visualization algorithms. This effort has already shown itself very useful to highlight essential features of the beam dynamics which remained unnoticed before. In this paper we present measurements results displaying beam dynamics process, and in particular space charge related process, happening in the central region of the TRIUMF cyclotron.

Poster TUPPT011 [32.212 MB]

TUPSH003

Conceptual Design of a 100 MeV Injector Cyclotron

cyclotron, proton, cavity, extraction

224

M. Li, J.J. Yang, T.J. Zhang, J.Q. Zhong
CIAE, Beijing, People's Republic of China

Accelerator driven system (ADS) is advanced clean nuclear energy system based on a high power accelerator, which has been proposed worldwide in recent years. Referring to the experiences from the existing PSI high power proton facility, an 800 MeV cyclotron is under design at CIAE (China Institute of Atomic Energy) as a candidate of high power proton driver. Given the extremely high beam power to be extracted, a tiny beam loss can lead to disastrous result for the cyclotron. Especially, the beam loss during extraction is the critical issue with respect to the feasibility and reliability of the design, which needs to be investigated in great detail from the very beginning. In this paper, the extraction scheme and beamline elements design are presented, and the detailed beam loss distribution during extraction will be calculated by numerical simulation with the large-scale parallel code OPAL-CYCL.

TUPSH008

Conceptual Design of the 100 MeV Separated Sector Cyclotron

cyclotron, simulation, extraction, magnet-design

236

B. Mahdian, H. Afarideh, R. Solhju
AUT, Tehran, Iran
J.-S. Chai, M. Ghergherehchi
SKKU, Suwon, Republic of Korea

The 100 MeV separated sector cyclotron was designed at Amirkabir University of Technology (AUT), which was aimed for various applications including radioactive ion-beam (RIB) production and proton therapy. It has four separated sector magnets. The cyclotron magnet design was based on an iterative process starting from a simple model that requires the vision of the complete cyclotron and the possibility of integration of all subsystems. By computer simulation with the 3D (CST) and 2D (POSSION) codes, principle parameters of the cyclotron magnet system were estimated (pole radius 180 cm, outer diameter 640 cm, height 300 cm). The results showed that the isochronous deviations between simulated values and the calculation one are smaller than 5 Gauss at most radii and therefore fulfilled the requirements. This work has been done with high accuracy which is proved by particle trajectories and considered mesh range. It has been concluded that it can be possible to design and develop this high energy cyclotron by introducing simple model without using trim and harmonic coils.

TU4PB01

Mapping of the New IBA Superconducting Synchrocyclotron (S2C2) for Proton Therapy

proton, extraction, synchro-cyclotron, cyclotron

272

J. van de Walle, W.J.G.M. Kleeven, C. L'Abbate, V. Nuttens, Y. Paradis
IBA, Louvain-la-Neuve, Belgium
M. Conjat, J. Mandrillon, P. Mandrillon
AIMA, Nice, France

The magnetic field in the Superconducting Synchrocyclotron (S2C2) has been measured with a newly developed mapping system during the commissioning of the machine at IBA. The major difference with other mapping systems at IBA is the usage of a search coil, which provides high linearity over a large magnetic field range and the possibility to measure in a more time economic way. The first mapping results of the S2C2 were compared with OPERA3D calculations. The average field, the tune functions and the first harmonic were the main quantities which were compared and showed good agreement with the model. For example, the average field was within 0.3% of the calculation over the entire machine. In order to assess the efficiency of the regenerative extraction mechanism, protons were tracked in the measured map up to extraction. The horizontal position of the main coil was found to be a crucial parameter for the optimization of the extraction. A dedicated linear mapping system consisting of 7 Hall probes was positioned in the extraction channel of the S2C2. The field values from this linear mapping system were used to assess the optics of the beam exiting the S2C2.

Slides TU4PB01 [2.357 MB]

WE1PB01

The Houghton College Cyclotron: a Tool for Educating Undergraduates

cyclotron, target, vacuum, ion

286

M.E. Yuly
Houghton College, Houghton, New York, USA

The cyclotron is an ideal undergraduate research project because its operation and use involve so many of the principles covered in the undergraduate physics curriculum – from resonant circuits to nuclear reactions. The physics program at Houghton College, as part of an emphasis on active learning, requires all majors to complete a multiyear research project culminating in an undergraduate thesis. Over the past ten years seven students have constructed a working 1.2 T tabletop cyclotron theoretically capable of producing approximately 400 keV protons. The construction and performance of the cyclotron will be discussed, as well as its use as an educational tool.

Slides WE1PB01 [28.909 MB]

WEPPT011

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

cyclotron, extraction, acceleration, 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.

WEPPT012

Beam Dynamics in Presence of Imperfection Fields Near the Extraction Zone of Kolkata Superconducting Cyclotron

extraction, cyclotron, simulation, betatron

347

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

Funding: VECC, DAE
The superconducting cyclotron at Kolkata has accelerated the ion beams up to the extraction radius producing neutrons via nuclear reactions. After that the beam extraction process has been tried exhaustively. But rigorous beam extraction trials indicate towards some kind of error field, which was not possible to balance with the trim coil operated in harmonic-coil mode. It is found that the beam is being off-centered by a large amount after crossing the resonance zone and it is not reaching the extraction radius in proper path. This paper will be emphasizing the effect of various kind of error field on the beam. However, the magnetic field is being measured again to know the exact distribution of the field.

WEPPT025

Beam Physics Demonstrations with the Rutgers 12-Inch Cyclotron

cyclotron, ion, betatron, focusing

369

T.W. Koeth
UMD, College Park, Maryland, USA

The Rutgers 12-Inch Cyclotron is a research grade accelerator dedicated to undergraduate education.[1] From its inception, it has been intended for instruction and has been designed to demonstrate classic beam physics phenomena. The machine is easily reconfigured, allowing experiments to be designed and performed within one academic semester. Our cyclotron gives students a hands-on opportunity to operate an accelerator and directly observe many fundamental beam physics concepts, including axial and radial betatron motion, destructive resonances, weak and azimuthally varying field (AVF) focusing schemes, DEE voltage effects, and more.

WE3PB01

Experimental Study of Resonance Crossing with a Paul Trap

emittance, 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]