SAP2023 - List of Keywords (proton)

Paper	Title	Other Keywords	Page
MOPB005	Design of Beam Dynamics for a High-Power DC Proton Accelerator at the MeV Level	focusing, space-charge, acceleration, neutron	24
	Z.-F. He, M.H. Zhao SINAP, Shanghai, People’s Republic of China W. Wan ShanghaiTech University, Shanghai, People’s Republic of China
	This paper aims to design the beam dynamics of a MeV-level high-power DC proton accelerator for use in high-voltage accelerators. The high-power proton accelerator has essential applications such as ion implantation equipment, neutron therapy equipment, and accelerator-based neutron source equipment. With the increasing use of high-voltage generators due to their stable and reliable operation, these accelerators have gained significant popularity in the field. The paper discusses the design considerations of the accelerator equipment, including the functions and requirements of the acceleration tube, electric field distribution, and voltage holding issues. Additionally, the paper focuses on the design aspects of beam optics, encompassing topics such as electric field distribution, beam focusing, beam transmission, divergence, and the impact of space charge effects on beam quality. Calculations and optimizations are performed based on the parameters and requirements specific to high-voltage accelerators. Finally, the paper presents and analyzes the results of the accelerator tube and beam optics design.
DOI •	reference for this paper ※ doi:10.18429/JACoW-SAP2023-MOPB005
About •	Received ※ 30 June 2023 — Revised ※ 09 July 2023 — Accepted ※ 11 July 2023 — Issued ※ 04 October 2024
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPB010	Dynamics Design on 70-250Mev Proton Linac	acceleration, linac, lattice, radiation	102
	Y.F. Yang, Z. Li, P.T. Lin, Z.Q. Ren, X.M. Wan SCU, Chengdu, People’s Republic of China
	Charged proton beams have broad application prospects, and research on compact S-band proton linear accelerators is increasingly heating up in recent years. For radiation therapy, to achieve the conventional penetration range of water-equivalent tissues, protons with energy of 70 to 230MeV are required. The design of electromagnetic structure is closely related to particle dynamics design. A flexible and controllable particle dynamic tracking code (PDT) through both traveling wave and standing wave acceleration has been compiled to simulate particle trajectory and satisfy automatic tuning of the various components in the entire acceleration chain. The linac with a total length of approximately 8.2m composed of 16 tanks of backward traveling wave structures and permanent magnet quadrupole lenses was designed, operating at an RF frequency of 2.856GHz with a target acceleration gradient of 30MV/m, and accelerating proton beam from 70MeV to 250MeV while maintaining low emittance and high transmission efficiency.
DOI •	reference for this paper ※ doi:10.18429/JACoW-SAP2023-TUPB010
About •	Received ※ 09 July 2023 — Accepted ※ 12 July 2023 — Issued ※ 11 August 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPB014	Design of a Large Momentum Acceptance Gantry Based on AG-CCT for Lightweight Proton Therapy Facility	toolkit, lattice, simulation, optics	111
	Y.C. Liao, X. Liu, R.Y. Luo, B. Qin, W. Wang HUST, Wuhan, People’s Republic of China
	Funding: This work was supported by the National Natural Science Foundation of China under Grant 11975107, 12205111. Superconducting (SC) gantry can be applied to proton therapy with significantly reduced footprint and weight. However, the relatively lower ramping limit of the SC magnetic field becomes a bottle-neck for fast energy change and beam delivery. The issue can be mitigated by designing a large momentum acceptance (LMA) beam optics. We present the design of an LMA gantry using AG-CCT SC magnets and symmetrical achromatic lattice. A fast degrader is combined in the design so that the gantry can rapidly switch energy during the treatment. The AG-CCT design process and beam transport simulation are all performed with our homemade integrated code CSPT, which has interfaces to Geant-4 and Opera, and can reach a maximum speed-up ratio of ~450 by applying parallel computation technique. The multi-particle simulation based on realistic field distribution proves that the gantry has a large momentum acceptance of ~20%. Due to its large momentum acceptance, the dispersion effect caused by the scanning magnet is not neglectable. A dispersion compensation method, accompanied by a compact nozzle layout, is proposed to achieve a scanning field of 25×25 cm² with a maximum beam energy spread of 5.2%.
DOI •	reference for this paper ※ doi:10.18429/JACoW-SAP2023-TUPB014
About •	Received ※ 28 June 2023 — Accepted ※ 11 July 2023 — Issued ※ 23 April 2024
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPB015	Research on First Harmonic Shimming Method of Cyclotron Based on Least Norm Square Solution	MMI, cyclotron, simulation, software	114
	J.R. Lu, S. An, T.J. Bian CIAE, Beijing, People’s Republic of China
	The magnetic field measurement of cyclotron and the shimming of isochronous magnetic field are one of the important links in cyclotron. Due to the influence of factors such as processing errors, installation errors, and inhomogeneity of the magnetic properties of mag-net materials, the main magnetic field of the cyclotron will usually deviate from the required isochronous magnetic field and contain a certain amplitude of the first harmonic magnetic field. The existence of the first harmonic magnetic field will rapidly increase the transverse oscillation amplitude and cyclic emittance of the particles, eventually causing beam loss. In order to improve the beam quality of the cyclotron, the shimming technology of the first harmonic magnetic field is essential. In this paper, through the finite element simulation calculation of the main magnet of the cyclotron, a quantitative algorithm for the first harmonic shimming based on the least norm square solution is proposed. At present, this method is being pre-pared for apply to the magnetic field shimming of the 10MeV high-current proton cyclotron of the CIAE.
DOI •	reference for this paper ※ doi:10.18429/JACoW-SAP2023-TUPB015
About •	Received ※ 29 June 2023 — Revised ※ 09 July 2023 — Accepted ※ 12 July 2023 — Issued ※ 18 September 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPB016	High-Fidelity Modeling and Transmission Optimization for the Beamline of HUST-PTF	simulation, beam-transport, vacuum, coupling	117
	Y.C. Chen, C.L. Liu, X. Liu, B. Qin, W. Wang HUST, Wuhan, People’s Republic of China
	A superconducting cyclotron-based proton therapy facility is under construction at Huazhong University of Science and Technology (HUST-PTF). In previous works, the vacuum chamber’s shape and the tail effect of the energy spectrum are not considered when calculating the transmission efficiency of the beamline. This study proposes a high-fidelity modeling and optimization method for the HUST-PTF beamline based on Monte Carlo simulation using BDSIM. The modeling procedure of the beamline based on BDSIM is briefly introduced. Then verification of the optical parameters are performed on the gantry sections, and the transmission efficiency of the gantry is optimized by analyzing the unexpected beam loss. After optimization, the transmission efficiency at each energy setting point is calculated. The simulation results show that (1) the proposed optimization method improves the gantry’s transmission efficiency from 92.4% to 95.6%; (2) the transmission efficiency calculated by high-fidelity modeling is more accurate than previous simulations because the beam-matter interaction and practical vacuum chamber geometry are considered.
DOI •	reference for this paper ※ doi:10.18429/JACoW-SAP2023-TUPB016
About •	Received ※ 29 June 2023 — Revised ※ 09 July 2023 — Accepted ※ 11 July 2023 — Issued ※ 09 February 2024
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPB017	Calibration Experiment of Equivalent Area of Induction Coil for Magnetic Field Measurement of Superconducting Cyclotron	induction, cyclotron, experiment, permanent-magnet	120
	X.Y. Chen, S. An, T.J. Bian, L. Ling, J.R. Lu, F. Wang CIAE, Beijing, People’s Republic of China
	China Institute of Atomic Energy’s 250MeV superconducting cyclotron (CYCIAE-250) uses the induction coil method to measure the magnetic field in its airgap. To ensure the precision of magnetic field measurement, area of the induction coil needs to be calibrated. This paper designs a set of coil calibration technique based on flipping coil method. The uniform magnetic field needed for calibration is provided by a permanent magnet with good static performance, its field is measured through high-precision nuclear magnetic resonance(NMR) probe. Then the induction coil will then be installed at the same position of the NMR probe. During the calibration process, induction coil is rotated 180 degrees and magnetic flux through it will be recorded by a high-speed digital integrator. Corresponding equipment is also designed to finish this task. This Paper describes this magnetic field measurement method, corresponding magnetic measurement equipment, calibration process of the induction coil and calibrated area of the coil.
	Poster TUPB017 [0.908 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-SAP2023-TUPB017
About •	Received ※ 10 July 2023 — Revised ※ 11 July 2023 — Accepted ※ 12 July 2023 — Issued ※ 01 March 2024
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPB018	The Design of Nonlinear Regenerative Extraction in 250MeV Protron Superconducting Synchrocyclotron	extraction, synchro-cyclotron, cyclotron, simulation	123
	P.T. Lin, Z. Li, W.L. Liao, X.B. Luo, Z.Q. Ren, X.M. Wan, Y.F. Yang SCU, Chengdu, People’s Republic of China
	The objective of this article is to apply the regenerative extraction system to a 250MeV proton superconducting synchrocyclotron. The parameters of the regenerative extraction system are determined by iteratively calculating the appropriate magnetic field and particle trajectory in the region where the magnetic field and particle trajectories interact. This is then combined with the magnetic channel system to achieve the extraction of the beam from the accelerator. In the article, the particle orbit dynamics analysis and the design of relevant parameters for the regenerative extraction system were successfully implemented using Matlab programming. The simulation results showed that the stability in the vertical direction has the greatest impact on the extraction efficiency and determination of the regenerative magnetic field parameters. In order to maximize the particle extraction efficiency, the radial displacement of particles in the last few turns should pass through two identical nodes.
DOI •	reference for this paper ※ doi:10.18429/JACoW-SAP2023-TUPB018
About •	Received ※ 09 July 2023 — Revised ※ 11 July 2023 — Accepted ※ 12 July 2023 — Issued ※ 04 July 2024
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPB021	The Design of a Proton-Heavy Ion Hybrid Synchrotron Upgraded from XiPAF Proton Ring	injection, synchrotron, heavy-ion, extraction	129
	H.J. Yao, Y. Li, X.Y. Liu, X.W. Wang, Z.J. Wang, S.X. Zheng TUB, Beijing, People’s Republic of China Z.M. Wang NINT, Shannxi, People’s Republic of China
	Xi’an 200MeV Proton Application Facility (XiPAF) has been basically completed at the end of 2020, providing proton beams of 10 to 200 MeV for space radiation effect studies on electronics. To expand its capabilities, XiPAF is undergoing an upgrade to deliver multiple ion species, from proton to Bismuth ion. The upgrade focuses on three aspects. First, the original negative hydrogen linear injector will be remodeled to a proton linear injector. Second, a heavy ion linear injector will be added. Third, the existing proton ring will be retrofitted into a hybrid proton-heavy ion synchrotron. Correspondingly, the beam transport lines will also be modified. This paper details the considerations and physical designs for upgrading the synchrotron. Within the scope, we discuss the challenges and solutions in transforming a specialized proton synchrotron into a multi-ion accelerator under the constraints of existing plant layout and reuse of existing equipment.
DOI •	reference for this paper ※ doi:10.18429/JACoW-SAP2023-TUPB021
About •	Received ※ 29 June 2023 — Revised ※ 09 July 2023 — Accepted ※ 12 July 2023 — Issued ※ 20 September 2024
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPB024	Electron Cooling for Future High-energy Hadron Accelerators	electron, wiggler, emittance, hadron	133
	H. Zhao IMP/CAS, Lanzhou, People’s Republic of China
	Funding: National Natural Science Foundation of China (No. 12275323) Electron cooling is an important method to reduce the emittance and momentum spread of hadron beams, and it has been successfully applied in several facilities around the world. In 2019, the world¿s first RF-based electron cooler (LEReC) was commissioned at BNL for the RHIC BES-II project, and the integrated luminosity of RHIC is finally doubled. In addition, electron cooling is also a must for the future Electron-Ion Collider (BNL EIC). However, the high energy requirement of the electron beam (150 MeV) is far beyond what all present coolers can achieve (<4.3 MeV). For that, an electron ring cooler with strong radiation damping is proposed and designed, in which the non-magnetized and dispersive cooling techniques are applied. In this talk, I will introduce the experimental and simulation results of the two facilities. Mainly, I will introduce several new phenomena that were first observed in LEReC, such as the beam heating effect and the ion beam focusing effect. Besides, some new theories that were developed for the ring cooler will also be discussed.
	Poster TUPB024 [1.769 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-SAP2023-TUPB024
About •	Received ※ 04 July 2023 — Revised ※ 09 July 2023 — Accepted ※ 11 July 2023 — Issued ※ 14 December 2023
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TUPB025	Influence of Transverse Distribution of Electron Beam on the Distribution of Proton Beam in the Process of Electron Cooling	electron, simulation, storage-ring, scattering	137
	X.D. Yang IMP/CAS, Lanzhou, People’s Republic of China
	Funding: National Natural Science Foundation of China No.12275325 The electron cooling process of 20GeV proton beam in EicC was simulated for the eight transverse distribution of electron beam with the help of electron cooling simulation code. The transverse cooling time was obtained in the different transverse distribution of electron beam. The final transverse distribution of proton beam was demonstrated. The simulated results reveal that the transverse distribution of electron beam influences the distribution of proton beam in the process of electron cooling. In the future, this idea was expected to apply to the longitudinal distribution of electron beam. The longitudinal distribution of proton beam was attempted to be controlled by the longitudinally modulated electron beam. As a result, the peak current and longitudinal distribution of proton beam will be controlled by the electron beam. The loss of proton beams will be reduced, and the stored lifetime of proton beam in the storage ring will be extended. The intensity of the proton beam will be maintained for a longer time.
	Poster TUPB025 [2.048 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-SAP2023-TUPB025
About •	Received ※ 28 June 2023 — Revised ※ 09 July 2023 — Accepted ※ 12 July 2023 — Issued ※ 06 June 2024
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TUPB026	Design of a Synchrotron for Proton FLASH Radiotherapy Based on Fast Variable-Energy Bunch Splitting	synchrotron, extraction, kicker, radiation	141
	Y. Li, X.W. Wang, Q.Z. Xing, H.J. Yao, S.X. Zheng TUB, Beijing, People’s Republic of China
	Ultra-high dose rate (FLASH) radiotherapy not only guarantees effective tumor treatment but also greatly enhances the protection of normal tissue. Moreover, it is a convenient procedure for tumor patients that has enhanced the benefits provided by medical institutions. Proton FLASH radiotherapy, which combines the Bragg peak effect of proton spatial dose distribution with the unique temporal effect advantage of FLASH, is an attractive tumor treatment approach. To achieve proton FLASH discrete pencil beam scanning in a 1-L volume, taking into account the 5-mm point interval, 9261 points would need to be irradiated within 500 ms, which is beyond the capability of existing medical devices. To meet these requirements, based on a fast cycle synchrotron with a period of 25 Hz, we simultaneously combined variable-energy, fast splitting, and extraction beam bunches, and proposed a scanning method suitable for continuous variable-energy extraction bunches. The proposed technique meet the requirements of proton FLASH discrete pencil beam scanning within a volume of 1 L.
DOI •	reference for this paper ※ doi:10.18429/JACoW-SAP2023-TUPB026
About •	Received ※ 29 June 2023 — Revised ※ 10 July 2023 — Accepted ※ 12 July 2023 — Issued ※ 28 May 2024
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Other Keywords

Page

MOPB005

Design of Beam Dynamics for a High-Power DC Proton Accelerator at the MeV Level

focusing, space-charge, acceleration, neutron

24

Z.-F. He, M.H. Zhao
SINAP, Shanghai, People’s Republic of China
W. Wan
ShanghaiTech University, Shanghai, People’s Republic of China

This paper aims to design the beam dynamics of a MeV-level high-power DC proton accelerator for use in high-voltage accelerators. The high-power proton accelerator has essential applications such as ion implantation equipment, neutron therapy equipment, and accelerator-based neutron source equipment. With the increasing use of high-voltage generators due to their stable and reliable operation, these accelerators have gained significant popularity in the field. The paper discusses the design considerations of the accelerator equipment, including the functions and requirements of the acceleration tube, electric field distribution, and voltage holding issues. Additionally, the paper focuses on the design aspects of beam optics, encompassing topics such as electric field distribution, beam focusing, beam transmission, divergence, and the impact of space charge effects on beam quality. Calculations and optimizations are performed based on the parameters and requirements specific to high-voltage accelerators. Finally, the paper presents and analyzes the results of the accelerator tube and beam optics design.

DOI •

reference for this paper ※ doi:10.18429/JACoW-SAP2023-MOPB005

About •

Received ※ 30 June 2023 — Revised ※ 09 July 2023 — Accepted ※ 11 July 2023 — Issued ※ 04 October 2024

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPB010

Dynamics Design on 70-250Mev Proton Linac

acceleration, linac, lattice, radiation

102

Y.F. Yang, Z. Li, P.T. Lin, Z.Q. Ren, X.M. Wan
SCU, Chengdu, People’s Republic of China

Charged proton beams have broad application prospects, and research on compact S-band proton linear accelerators is increasingly heating up in recent years. For radiation therapy, to achieve the conventional penetration range of water-equivalent tissues, protons with energy of 70 to 230MeV are required. The design of electromagnetic structure is closely related to particle dynamics design. A flexible and controllable particle dynamic tracking code (PDT) through both traveling wave and standing wave acceleration has been compiled to simulate particle trajectory and satisfy automatic tuning of the various components in the entire acceleration chain. The linac with a total length of approximately 8.2m composed of 16 tanks of backward traveling wave structures and permanent magnet quadrupole lenses was designed, operating at an RF frequency of 2.856GHz with a target acceleration gradient of 30MV/m, and accelerating proton beam from 70MeV to 250MeV while maintaining low emittance and high transmission efficiency.

DOI •

reference for this paper ※ doi:10.18429/JACoW-SAP2023-TUPB010

About •

Received ※ 09 July 2023 — Accepted ※ 12 July 2023 — Issued ※ 11 August 2023

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPB014

Design of a Large Momentum Acceptance Gantry Based on AG-CCT for Lightweight Proton Therapy Facility

toolkit, lattice, simulation, optics

111

Y.C. Liao, X. Liu, R.Y. Luo, B. Qin, W. Wang
HUST, Wuhan, People’s Republic of China

Funding: This work was supported by the National Natural Science Foundation of China under Grant 11975107, 12205111.
Superconducting (SC) gantry can be applied to proton therapy with significantly reduced footprint and weight. However, the relatively lower ramping limit of the SC magnetic field becomes a bottle-neck for fast energy change and beam delivery. The issue can be mitigated by designing a large momentum acceptance (LMA) beam optics. We present the design of an LMA gantry using AG-CCT SC magnets and symmetrical achromatic lattice. A fast degrader is combined in the design so that the gantry can rapidly switch energy during the treatment. The AG-CCT design process and beam transport simulation are all performed with our homemade integrated code CSPT, which has interfaces to Geant-4 and Opera, and can reach a maximum speed-up ratio of ~450 by applying parallel computation technique. The multi-particle simulation based on realistic field distribution proves that the gantry has a large momentum acceptance of ~20%. Due to its large momentum acceptance, the dispersion effect caused by the scanning magnet is not neglectable. A dispersion compensation method, accompanied by a compact nozzle layout, is proposed to achieve a scanning field of 25×25 cm² with a maximum beam energy spread of 5.2%.

DOI •

reference for this paper ※ doi:10.18429/JACoW-SAP2023-TUPB014

About •

Received ※ 28 June 2023 — Accepted ※ 11 July 2023 — Issued ※ 23 April 2024

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TUPB015

Research on First Harmonic Shimming Method of Cyclotron Based on Least Norm Square Solution

MMI, cyclotron, simulation, software

114

J.R. Lu, S. An, T.J. Bian
CIAE, Beijing, People’s Republic of China

The magnetic field measurement of cyclotron and the shimming of isochronous magnetic field are one of the important links in cyclotron. Due to the influence of factors such as processing errors, installation errors, and inhomogeneity of the magnetic properties of mag-net materials, the main magnetic field of the cyclotron will usually deviate from the required isochronous magnetic field and contain a certain amplitude of the first harmonic magnetic field. The existence of the first harmonic magnetic field will rapidly increase the transverse oscillation amplitude and cyclic emittance of the particles, eventually causing beam loss. In order to improve the beam quality of the cyclotron, the shimming technology of the first harmonic magnetic field is essential. In this paper, through the finite element simulation calculation of the main magnet of the cyclotron, a quantitative algorithm for the first harmonic shimming based on the least norm square solution is proposed. At present, this method is being pre-pared for apply to the magnetic field shimming of the 10MeV high-current proton cyclotron of the CIAE.

DOI •

reference for this paper ※ doi:10.18429/JACoW-SAP2023-TUPB015

About •

Received ※ 29 June 2023 — Revised ※ 09 July 2023 — Accepted ※ 12 July 2023 — Issued ※ 18 September 2023

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPB016

High-Fidelity Modeling and Transmission Optimization for the Beamline of HUST-PTF

simulation, beam-transport, vacuum, coupling

117

Y.C. Chen, C.L. Liu, X. Liu, B. Qin, W. Wang
HUST, Wuhan, People’s Republic of China

A superconducting cyclotron-based proton therapy facility is under construction at Huazhong University of Science and Technology (HUST-PTF). In previous works, the vacuum chamber’s shape and the tail effect of the energy spectrum are not considered when calculating the transmission efficiency of the beamline. This study proposes a high-fidelity modeling and optimization method for the HUST-PTF beamline based on Monte Carlo simulation using BDSIM. The modeling procedure of the beamline based on BDSIM is briefly introduced. Then verification of the optical parameters are performed on the gantry sections, and the transmission efficiency of the gantry is optimized by analyzing the unexpected beam loss. After optimization, the transmission efficiency at each energy setting point is calculated. The simulation results show that (1) the proposed optimization method improves the gantry’s transmission efficiency from 92.4% to 95.6%; (2) the transmission efficiency calculated by high-fidelity modeling is more accurate than previous simulations because the beam-matter interaction and practical vacuum chamber geometry are considered.

DOI •

reference for this paper ※ doi:10.18429/JACoW-SAP2023-TUPB016

About •

Received ※ 29 June 2023 — Revised ※ 09 July 2023 — Accepted ※ 11 July 2023 — Issued ※ 09 February 2024

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPB017

Calibration Experiment of Equivalent Area of Induction Coil for Magnetic Field Measurement of Superconducting Cyclotron

induction, cyclotron, experiment, permanent-magnet

120

X.Y. Chen, S. An, T.J. Bian, L. Ling, J.R. Lu, F. Wang
CIAE, Beijing, People’s Republic of China

China Institute of Atomic Energy’s 250MeV superconducting cyclotron (CYCIAE-250) uses the induction coil method to measure the magnetic field in its airgap. To ensure the precision of magnetic field measurement, area of the induction coil needs to be calibrated. This paper designs a set of coil calibration technique based on flipping coil method. The uniform magnetic field needed for calibration is provided by a permanent magnet with good static performance, its field is measured through high-precision nuclear magnetic resonance(NMR) probe. Then the induction coil will then be installed at the same position of the NMR probe. During the calibration process, induction coil is rotated 180 degrees and magnetic flux through it will be recorded by a high-speed digital integrator. Corresponding equipment is also designed to finish this task. This Paper describes this magnetic field measurement method, corresponding magnetic measurement equipment, calibration process of the induction coil and calibrated area of the coil.

Poster TUPB017 [0.908 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-SAP2023-TUPB017

About •

Received ※ 10 July 2023 — Revised ※ 11 July 2023 — Accepted ※ 12 July 2023 — Issued ※ 01 March 2024

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPB018

The Design of Nonlinear Regenerative Extraction in 250MeV Protron Superconducting Synchrocyclotron

extraction, synchro-cyclotron, cyclotron, simulation

123

P.T. Lin, Z. Li, W.L. Liao, X.B. Luo, Z.Q. Ren, X.M. Wan, Y.F. Yang
SCU, Chengdu, People’s Republic of China

The objective of this article is to apply the regenerative extraction system to a 250MeV proton superconducting synchrocyclotron. The parameters of the regenerative extraction system are determined by iteratively calculating the appropriate magnetic field and particle trajectory in the region where the magnetic field and particle trajectories interact. This is then combined with the magnetic channel system to achieve the extraction of the beam from the accelerator. In the article, the particle orbit dynamics analysis and the design of relevant parameters for the regenerative extraction system were successfully implemented using Matlab programming. The simulation results showed that the stability in the vertical direction has the greatest impact on the extraction efficiency and determination of the regenerative magnetic field parameters. In order to maximize the particle extraction efficiency, the radial displacement of particles in the last few turns should pass through two identical nodes.

DOI •

reference for this paper ※ doi:10.18429/JACoW-SAP2023-TUPB018

About •

Received ※ 09 July 2023 — Revised ※ 11 July 2023 — Accepted ※ 12 July 2023 — Issued ※ 04 July 2024

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPB021

The Design of a Proton-Heavy Ion Hybrid Synchrotron Upgraded from XiPAF Proton Ring

injection, synchrotron, heavy-ion, extraction

129

H.J. Yao, Y. Li, X.Y. Liu, X.W. Wang, Z.J. Wang, S.X. Zheng
TUB, Beijing, People’s Republic of China
Z.M. Wang
NINT, Shannxi, People’s Republic of China

Xi’an 200MeV Proton Application Facility (XiPAF) has been basically completed at the end of 2020, providing proton beams of 10 to 200 MeV for space radiation effect studies on electronics. To expand its capabilities, XiPAF is undergoing an upgrade to deliver multiple ion species, from proton to Bismuth ion. The upgrade focuses on three aspects. First, the original negative hydrogen linear injector will be remodeled to a proton linear injector. Second, a heavy ion linear injector will be added. Third, the existing proton ring will be retrofitted into a hybrid proton-heavy ion synchrotron. Correspondingly, the beam transport lines will also be modified. This paper details the considerations and physical designs for upgrading the synchrotron. Within the scope, we discuss the challenges and solutions in transforming a specialized proton synchrotron into a multi-ion accelerator under the constraints of existing plant layout and reuse of existing equipment.

DOI •

reference for this paper ※ doi:10.18429/JACoW-SAP2023-TUPB021

About •

Received ※ 29 June 2023 — Revised ※ 09 July 2023 — Accepted ※ 12 July 2023 — Issued ※ 20 September 2024

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPB024

Electron Cooling for Future High-energy Hadron Accelerators

electron, wiggler, emittance, hadron

133

H. Zhao
IMP/CAS, Lanzhou, People’s Republic of China

Funding: National Natural Science Foundation of China (No. 12275323)
Electron cooling is an important method to reduce the emittance and momentum spread of hadron beams, and it has been successfully applied in several facilities around the world. In 2019, the world¿s first RF-based electron cooler (LEReC) was commissioned at BNL for the RHIC BES-II project, and the integrated luminosity of RHIC is finally doubled. In addition, electron cooling is also a must for the future Electron-Ion Collider (BNL EIC). However, the high energy requirement of the electron beam (150 MeV) is far beyond what all present coolers can achieve (<4.3 MeV). For that, an electron ring cooler with strong radiation damping is proposed and designed, in which the non-magnetized and dispersive cooling techniques are applied. In this talk, I will introduce the experimental and simulation results of the two facilities. Mainly, I will introduce several new phenomena that were first observed in LEReC, such as the beam heating effect and the ion beam focusing effect. Besides, some new theories that were developed for the ring cooler will also be discussed.

Poster TUPB024 [1.769 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-SAP2023-TUPB024

About •

Received ※ 04 July 2023 — Revised ※ 09 July 2023 — Accepted ※ 11 July 2023 — Issued ※ 14 December 2023

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TUPB025

Influence of Transverse Distribution of Electron Beam on the Distribution of Proton Beam in the Process of Electron Cooling

electron, simulation, storage-ring, scattering

137

X.D. Yang
IMP/CAS, Lanzhou, People’s Republic of China

Funding: National Natural Science Foundation of China No.12275325
The electron cooling process of 20GeV proton beam in EicC was simulated for the eight transverse distribution of electron beam with the help of electron cooling simulation code. The transverse cooling time was obtained in the different transverse distribution of electron beam. The final transverse distribution of proton beam was demonstrated. The simulated results reveal that the transverse distribution of electron beam influences the distribution of proton beam in the process of electron cooling. In the future, this idea was expected to apply to the longitudinal distribution of electron beam. The longitudinal distribution of proton beam was attempted to be controlled by the longitudinally modulated electron beam. As a result, the peak current and longitudinal distribution of proton beam will be controlled by the electron beam. The loss of proton beams will be reduced, and the stored lifetime of proton beam in the storage ring will be extended. The intensity of the proton beam will be maintained for a longer time.

Poster TUPB025 [2.048 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-SAP2023-TUPB025

About •

Received ※ 28 June 2023 — Revised ※ 09 July 2023 — Accepted ※ 12 July 2023 — Issued ※ 06 June 2024

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TUPB026

Design of a Synchrotron for Proton FLASH Radiotherapy Based on Fast Variable-Energy Bunch Splitting

synchrotron, extraction, kicker, radiation

141

Y. Li, X.W. Wang, Q.Z. Xing, H.J. Yao, S.X. Zheng
TUB, Beijing, People’s Republic of China

Ultra-high dose rate (FLASH) radiotherapy not only guarantees effective tumor treatment but also greatly enhances the protection of normal tissue. Moreover, it is a convenient procedure for tumor patients that has enhanced the benefits provided by medical institutions. Proton FLASH radiotherapy, which combines the Bragg peak effect of proton spatial dose distribution with the unique temporal effect advantage of FLASH, is an attractive tumor treatment approach. To achieve proton FLASH discrete pencil beam scanning in a 1-L volume, taking into account the 5-mm point interval, 9261 points would need to be irradiated within 500 ms, which is beyond the capability of existing medical devices. To meet these requirements, based on a fast cycle synchrotron with a period of 25 Hz, we simultaneously combined variable-energy, fast splitting, and extraction beam bunches, and proposed a scanning method suitable for continuous variable-energy extraction bunches. The proposed technique meet the requirements of proton FLASH discrete pencil beam scanning within a volume of 1 L.

DOI •

reference for this paper ※ doi:10.18429/JACoW-SAP2023-TUPB026

About •

Received ※ 29 June 2023 — Revised ※ 10 July 2023 — Accepted ※ 12 July 2023 — Issued ※ 28 May 2024

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