CYCLOTRONS2022 - List of Keywords (electron)

Paper	Title	Other Keywords	Page
MOBO03	Proton Irradiation Site for High-Uniformity Radiation Hardness Tests of Silicon Detectors at the Bonn Isochronous Cyclotron	radiation, cyclotron, site, proton	38
	D. Sauerland, R. Beck, P.D. Eversheim HISKP, Bonn, Germany J. Dingfelder, P. Wolf SiLab, Bonn, Germany
	The Bonn Isochronous Cyclotron provides proton, deuteron, alpha particle and other light ion beams, having a charge-to-mass ratio Q/A >= 1/2, with kinetic energies in the range of 7 to 14 MeV per nucleon. At the irradiation site, a 14 MeV proton beam with a diameter of a few mm is used to irradiate detectors, so-called devices under test (DUTs), housed in a thermally-insulated and gas-cooled box. To ensure homogeneous damage application, the DUT is moved through the beam in a row-wise scan pattern with constant velocity and a row separation, smaller than the beam diameter. During irradiation, beam parameters are continuously measured non-destructively using a calibrated, secondary electron emission-based beam monitor, installed at the exit to the site. This allows a beam-driven irradiation scheme, enabling the setup to autonomously react to changing beam conditions, resulting in highly-uniform proton fluence distributions with relative uncertainties of typically 2%. In this work, the accelerator facility is introduced, the proton irradiation site with focus on its beam diagnostics is presented in detail and resulting fluence distributions are shown.
	Slides MOBO03 [17.472 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-CYCLOTRONS2022-MOBO03
About •	Received ※ 31 December 2022 — Revised ※ 16 January 2023 — Accepted ※ 01 February 2023 — Issue date ※ 07 February 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOBO04	Experimental Study on Proton Irradiation Effect of Gallium Nitride High Electron Mobility Transistor	proton, radiation, experiment, ECR	42
	z. Zhang, Q. Chen, G. Guo, C.C. Liu CIAE, Beijing, People’s Republic of China
	As a third-generation semiconductor material, gallium nitride (GaN) has the advantages of high breakdown electric field, high electron saturation speed, high operating temperature and strong radiation resistance, and has broad application prospects in the aerospace field. As an important member of GaN-based electronic devices, GaN high electron mobility transistor (HEMT) is widely considered to be used in the power supply and other important systems of spacecraft. Therefore, GaN HEMT is of great significance for spacecraft to complete relevant setting tasks. However, GaN HEMT will inevitably be affected by space radiation environment when spacecraft perform related missions. Previous researches have shown that protons are the majority of high-energy particles in space environment. Therefore, relevant studies should focus on the effect of proton irradiation on the performance of GaN HEMT. Using 100 MeV high-current proton cyclotron, we investigated the proton irradiation effect of GaN HEMT, and proved the effect of proton energy on static electrical parameters of GaN. The research work in this paper lays a foundation for the future application of GaN HEMT in space missions.
	Slides MOBO04 [2.860 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-CYCLOTRONS2022-MOBO04
About •	Received ※ 15 December 2022 — Revised ※ 14 February 2023 — Accepted ※ 17 February 2023 — Issue date ※ 18 April 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPO004	Beam Dump Development for High Power Proton and Electron Beam	proton, target, cavity, controls	54
	J.Y. Liu, H.R. Cai, M.Z. Hu, G.F. Pan, S. Pei, G.F. Song, L. Wang, Y. Wang, S.M. Wei, Z.G. Yin, S.P. Zhang, T.J. Zhang, X.F. Zhu CIAE, Beijing, People’s Republic of China
	The high-intensity 100 MeV proton cyclotron CYCIAE-100 had provided 52 kW beam to the beam dump in 2018, is planning to upgrade at China Institute of Atomic Energy(CIAE). It is designed to provide a 75~100 MeV, 1 mA proton beam. So, a new beam dump for higher beam power have been developed since 2020. At the same time, a 1:4 scale, RF cavity with Q value up to 42000, is constructed for the engineering feasibility verification of a 2 GeV/6 MW CW FFAG, which is also being considered as a main accelerating cavity of a 100 kW electron accelerator. The electron beam will be rotated and accelerated 7 times by the gradient dipoles and the high Q cavity. The beam dump is designed to also use for the 100kW electron beam. With the same-level beam power of the two accelerators above the content, a beam dump for absorbing two kinds of particle beams according to the characteristics of the modification was designed. The energy deposition of 100MeV proton beam and 5MeV electron beam in the beam dump was investigated by the Monte-Carlo simulation program FLUKA. The beam dump cooling structure was optimizing by ICEM-CFD and fluent, so that the beam dump temperature was controlled less than 100°C, and the maximum temperature on the beam dump is less than 450°C. The beam dump is designed as a cube (450200200, unit:mm) with two 2.5°V-type copper pentagon and two flat parts. All the details about the simulation of energy deposition, thermal distribution and structure design will be presented in the paper.
	Poster MOPO004 [3.428 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-CYCLOTRONS2022-MOPO004
About •	Received ※ 31 December 2022 — Revised ※ 26 January 2023 — Accepted ※ 09 February 2023 — Issue date ※ 25 June 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPO011	Design and Operation of the New Fast Beam Chopper between Tandetron and Cyclotron	controls, power-supply, electronics, vacuum	76
	T. Fanselow, J. Bundesmann, A. Denker, A. Dittwald, U. Hiller HZB, Berlin, Germany
	In collaboration with Charite - Universitätsmedizin Berlin, patients with ocular melanomas are treated with protons at Helmholtz Zentrum Berlin. Accompanying research includes beam delivery for Flash irradiation, thus it became necessary to set up a fast and reliable beam chopper. The new beam chopper can deliver much shorter pulses than needed for Flash irradiation, minimum pulse widths down to 70ns at 1kV amplitude can be delivered. A short description of the design and installation process, which occurred in 2020, and the experiences of the first 2 years of operation with the new fast beam chopper system is presented.
	Poster MOPO011 [3.738 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-CYCLOTRONS2022-MOPO011
About •	Received ※ 30 December 2022 — Revised ※ 12 January 2023 — Accepted ※ 01 February 2023 — Issue date ※ 04 July 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPO012	An Embedded Beam Diagnostic Electronics for 230 MeV Superconducting Cyclotron Radial Probe and Scanning Wires	electronics, cyclotron, diagnostics, embedded	80
	T.Y. Jiang, P. Liu, X. Mu, Q.Q. Song, Y. Wang, Z.G. Yin, T.J. Zhang CIAE, Beijing, People’s Republic of China
	For the 230MeV superconducting cyclotron, once again, the differential radial probe has been proven to be crucial for the beam commission procedure. It can provide various information about the particles inside the cyclotron, such as the vertical position, the relative intensity as well as the oscillation frequency and radius, etc. In practice, however, the electronics system suffered from the leaking alternating RF field as well as the static magnetic field. Besides the EM shielding, an absorptive high-frequency filter has been included as the first element of the readout electronics. A high dynamic range readout electronic unit has been included to adapt to the fluctuation of the beam in the hole commissioning phase. The electronics box is designed as a network-attached embedded device so that it can be powered by a POE switch and transmits measurement results via MODBUS protocol. A dedicated digital signal processor and calibration units are also included, together with the ADCs, to facilitate the daily calibration process. The same electronics are used for the beamline wire scan system to determine the position of the beam, with a small improvement at a lower range. The design of this multi-purpose beam diagnostics electronics will be reviewed in this paper, together with several measurement results. zhiguoyin@ciae.ac.cn
	Poster MOPO012 [0.721 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-CYCLOTRONS2022-MOPO012
About •	Received ※ 01 January 2023 — Revised ※ 27 January 2023 — Accepted ※ 09 February 2023 — Issue date ※ 27 April 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPO008	H^- Intra-Beam Stripping Loss Rate in Isochronous Cyclotron	cyclotron, linac, resonance, target	219
	Y.-N. Rao TRIUMF, Vancouver, Canada
	Funding: This work was funded by TRIUMF which receives federal funding via a contribution agreement with the National Research Council of Canada. Binary collisions inside a H^- bunch result in H^- stripping and subsequent particle loss. This phenomenon, called intra-beam stripping, was observed in LEAR and SNS superconducting linac. We mimic the derivation made for the linac to derive the intra-beam stripping loss rate for an isochronous cyclotron. And then, we apply this theory to the TRIUMF 500 MeV H^- cyclotron to estimate the loss.
	Poster WEPO008 [1.189 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-CYCLOTRONS2022-WEPO008
About •	Received ※ 05 December 2022 — Revised ※ 04 February 2023 — Accepted ※ 07 February 2023 — Issue date ※ 14 July 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPO016	A New 18 GHz ECR Ion Source for Cyclotron at CIAE	ion-source, ECR, cyclotron, injection	234
	B. Tang, L.H. Chen, B.Q. Cui, G. Guo, R. Ma, Y.J. Ma, L. Sui, Y.F. Wang, L. Zhang CIAE, Beijing, People’s Republic of China Z.H. Jia, L.B. Li, Y.T. Li, W. Lu, J.D. Ma, P. Peng, C. Qian, L.T. Sun, P. Zhang, X.Z. Zhang IMP/CAS, Lanzhou, People’s Republic of China
	In order to meet the requirements of ion beam for the single event effect experiment, the ion source needs to supply ion beams of N, Ne, Si, Ar, Fe, Kr, Xe, and so on for the cyclotron. The most effective way to increase the energy of the cyclotron is to increase the charged state, and the Kr ion charge state reaches +22 while the Xe ion charge state reaches +35. A new room-temperature Electron Cyclotron Resonance (ECR) ion source operating at 18 GHz has been developed and assembled at CIAE. This new ECR ion source is based on the Lanzhou Electron Cyclotron Resonance ion source No.5 (LECR5) developed at IMP. The magnetic confinement of the new ECR ion source is realized by the axial mirror field provided by two set of room temperature pancake coils while the radial hexapole field is supplied by a permanent magnet hexapole. A multi-sputter disk injection component was designed for the production of metallic cocktail ion beams. This paper will give the detailed design of this ion source, and some preliminary highly charged ion beam production results will also be presented.
	Poster WEPO016 [0.654 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-CYCLOTRONS2022-WEPO016
About •	Received ※ 11 February 2023 — Revised ※ 13 February 2023 — Accepted ※ 20 February 2023 — Issue date ※ 01 July 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPO017	A New Design of CYCIAE230 Superconducting Cyclotron RF-Driven System	cyclotron, cavity, coupling, resonance	237
	Z.G. Yin, X.L. Fu, B. Ji, X. Mu, S. Pei, J.Y. Wei, T.J. Zhang CIAE, Beijing, People’s Republic of China
	A superconducting cyclotron with a beam energy of 246.2MeV has been developed and commissioned by the China Institute of Atomic Energy. The RF system of the first CYCIAE-230 cyclotron adopts two tetrode amplifiers to drive the cavities simultaneously. The driven power is 180 degrees out of phase and each of the amplifiers was designed able to deliver 75kW RF power to the cavities. In practice, it was found that the driven power is beyond necessary and only 80kW RF power is required for the beam. Hence, an upgrade of the existing RF-driven system to the stare-of-art of solid-state technology is put forward by the CIAE cyclotron team. Furthermore, this alternative design also includes an optimization of the coupling between amplifiers and the cavities, since the old coupler shows nonidealities under long-term high-power operations. A driven schema utilizing multiple low-power capacitive couplers is designed to address this issue, taking advantage of the cavity as a power combiner. In this paper, a review of the existing RF-driven system will be given first. It will be followed by an analysis of the limitation of such a system in practice. A new design of the solid amplifier, the new driven method, and a capacitive window will also be reported.
DOI •	reference for this paper ※ doi:10.18429/JACoW-CYCLOTRONS2022-WEPO017
About •	Received ※ 25 December 2022 — Revised ※ 29 January 2023 — Accepted ※ 09 February 2023 — Issue date ※ 02 June 2023
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WEPO018	Progress in the Design of a New 150-MHz Flat Top Cavity for the PSI RING Cyclotron	cavity, cyclotron, flattop, multipactoring	241
	J.-Y. Raguin, M. Bopp, R.F. Fortunati, J. Grillenberger, T.G. Lucas, M. Pedrozzi, M. Schneider, M. Stoll PSI, Villigen PSI, Switzerland E. Solodko Transmutex SA, Vernier, Switzerland
	Increasing PSI’s 590 MeV main cyclotron beam current to 3 mA requires the replacement of the existing power-limited 150 MHz flat top cavity with a new cavity. This new cavity has been designed to withstand a 700 kV peak voltage and a 140 kW dissipated average power. Although very similar in its geometry to the original flat top cavity currently in operation, in the new design, special attention has been paid to the shaping of the four electrodes for maximizing the shunt impedance. Furthermore, the topology of the cooling water channels has been optimized to increase the power handling capabilities of the cavity. Finally, in order to mitigate multipacting observed in the current design, variations on the new cavity baseline geometry have started to be explored.
	Poster WEPO018 [4.072 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-CYCLOTRONS2022-WEPO018
About •	Received ※ 30 November 2022 — Revised ※ 13 January 2023 — Accepted ※ 01 February 2023 — Issue date ※ 12 March 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPO002	Study on Proton Radiation Effect and Self-Repair of SiC-JBS Diodes	radiation, proton, ECR, interface	291
	C.C. Liu, Q. Chen, G. Guo, H.L. Shi, F.Q. Zhang, z. Zhang CIAE, Beijing, People’s Republic of China
	Funding: CNNC "Young Talents" Scientific Research Project (11FY212306000801) In this study, the influence of proton irradiation experiments at 40 MeV and p/cm² on Silicon Carbide Junction Barrier Schottky (SiC-JBS) diodes with stripe cell and hexagonal cell designs was investigated, respectively. Considering the displacement damage effect of SiC-JBS diodes, the experiments was implemented on unbiased SiC-JBS diodes based on 100 MeV high intensity proton cyclotron of China Institute of Atomic Energy. The results show that the current voltage (IV) and capacitive voltage (CV) characteristics of the SiC-JBS diodes are obviously degraded by proton irradiation. After 168 h of room temperature annealing, the forward IV characteristics of the SiC-JBS diodes are basically restored but the reverse leakage current is increased. After 336 h of room temperature annealing, the forward IV characteristic of the diodes is completely restored, but the reserve IV characteristic of the diodes with stripe cell is completely restored. And the CV characteristic is degraded of the two kinds of SiC-JBS diodes permanently, which indicating that room temperature annealing cannot restore the proton radiation displacement damage defects. Combined with Monte Carlo simulations, it is shown that proton irradiation will introduce ionization defects and displacement defects into the SiC-JBS diodes, in which the disappearance of displacement damage defects will eventually lead to the degradation of electrical properties of reverse IV and CV. The analysis of the SiC-JBS diodes structure shows that, without considering the diode materials and process level, the SiC-JBS diode with hexagonal cells is more resistant to proton irradiation displacement damage and has stronger room temperature annealing self-repair ability than the SiC-JBS diodes with stripe cells, even though its chip area is smaller. On the other hand, the SiC-JBS diodes with hexagonal cells can be used preferentially in the radiation environment where there is a large amount of proton.
	Poster THPO002 [5.018 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-CYCLOTRONS2022-THPO002
About •	Received ※ 21 December 2022 — Revised ※ 21 January 2023 — Accepted ※ 14 March 2023 — Issue date ※ 14 April 2023
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THPO003	Applications of the CYCIAE-100 Cyclotron in Neutron-Induced Single Event Effect	neutron, proton, radiation, target	295
	Q. Chen, J. Bao, G. Guo, J.H. Han, X. Ma, H.Y. Zhao CIAE, Beijing, People’s Republic of China
	Neutron-induced single event effect is one of the significant factors affecting the reliability of semiconductor devices in avionics and ground facilities. The 100 MeV proton cyclotron in China Institute of Atomic Energy (Cyciae-100) provides white neutron and quasi-monoenergetic neutron induced by proton and W/Li bombardment. Based on the white neutron beam line of Cyciae-100, the white neutron energy spectrum is measured by neutron time-of-flight method with double scintillator spectrometer, as well as the theoretical energy spectrum calculated by the Monte Carlo method. The neutron irradiation test of two SRAMs with different technology nodes were carried out, and the neutron single event upset sections are obtained simultaneously. In addition, based on the quasi-monoenergetic neutron beam line, the simulation of neutron energy spectrum and experimental measurement of neutron single event upset cross section for SRAMs were carried out. As a conclusion, the white neutron and quasi-monoenergetic neutron provided by Cyciae-100 are well suitable applied to the study of neutron single event effects.
	Poster THPO003 [0.726 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-CYCLOTRONS2022-THPO003
About •	Received ※ 31 December 2022 — Revised ※ 21 January 2023 — Accepted ※ 31 January 2023 — Issue date ※ 02 April 2023
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THPO008	Consideration of Using Non-Destructive Detectors in the Beamline of a Proton Therapy Facility	proton, cyclotron, detector, cavity	314
	Q.S. Chen, A.T. Chen, B. Qin HUST, Wuhan, People’s Republic of China
	Funding: This work is supported by the National Science Foundation of China under the contract No. 12175077. Ionization profile monitors (IPM) are a kind of nondestructive monitors mostly used in accelerators of high intensity pulsed beams. As for particle therapy accelerators, either based on cyclotrons or synchrotrons, the extracted beams are very weak, usually on the level of nano-Amperes. Up to date, the commonly used detectors in such low current machines are all destructive, such as fluorescent screens and gas ionization chambers. In this paper, we proposed for the first time to use a residual gas ionization monitor to measure the beam profiles in a proton therapy facility based on a superconducting cyclotron. The feasibility of such a scheme and some basic issues are discussed in this paper.
	Poster THPO008 [0.535 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-CYCLOTRONS2022-THPO008
About •	Received ※ 30 December 2022 — Revised ※ 13 February 2023 — Accepted ※ 19 February 2023 — Issue date ※ 07 June 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Other Keywords

Page

Proton Irradiation Site for High-Uniformity Radiation Hardness Tests of Silicon Detectors at the Bonn Isochronous Cyclotron

radiation, cyclotron, site, proton

38

D. Sauerland, R. Beck, P.D. Eversheim
HISKP, Bonn, Germany
J. Dingfelder, P. Wolf
SiLab, Bonn, Germany

The Bonn Isochronous Cyclotron provides proton, deuteron, alpha particle and other light ion beams, having a charge-to-mass ratio Q/A >= 1/2, with kinetic energies in the range of 7 to 14 MeV per nucleon. At the irradiation site, a 14 MeV proton beam with a diameter of a few mm is used to irradiate detectors, so-called devices under test (DUTs), housed in a thermally-insulated and gas-cooled box. To ensure homogeneous damage application, the DUT is moved through the beam in a row-wise scan pattern with constant velocity and a row separation, smaller than the beam diameter. During irradiation, beam parameters are continuously measured non-destructively using a calibrated, secondary electron emission-based beam monitor, installed at the exit to the site. This allows a beam-driven irradiation scheme, enabling the setup to autonomously react to changing beam conditions, resulting in highly-uniform proton fluence distributions with relative uncertainties of typically 2%. In this work, the accelerator facility is introduced, the proton irradiation site with focus on its beam diagnostics is presented in detail and resulting fluence distributions are shown.

Slides MOBO03 [17.472 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-CYCLOTRONS2022-MOBO03

About •

Received ※ 31 December 2022 — Revised ※ 16 January 2023 — Accepted ※ 01 February 2023 — Issue date ※ 07 February 2023

Cite •

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

MOBO04

Experimental Study on Proton Irradiation Effect of Gallium Nitride High Electron Mobility Transistor

proton, radiation, experiment, ECR

42

z. Zhang, Q. Chen, G. Guo, C.C. Liu
CIAE, Beijing, People’s Republic of China

As a third-generation semiconductor material, gallium nitride (GaN) has the advantages of high breakdown electric field, high electron saturation speed, high operating temperature and strong radiation resistance, and has broad application prospects in the aerospace field. As an important member of GaN-based electronic devices, GaN high electron mobility transistor (HEMT) is widely considered to be used in the power supply and other important systems of spacecraft. Therefore, GaN HEMT is of great significance for spacecraft to complete relevant setting tasks. However, GaN HEMT will inevitably be affected by space radiation environment when spacecraft perform related missions. Previous researches have shown that protons are the majority of high-energy particles in space environment. Therefore, relevant studies should focus on the effect of proton irradiation on the performance of GaN HEMT. Using 100 MeV high-current proton cyclotron, we investigated the proton irradiation effect of GaN HEMT, and proved the effect of proton energy on static electrical parameters of GaN. The research work in this paper lays a foundation for the future application of GaN HEMT in space missions.

Slides MOBO04 [2.860 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-CYCLOTRONS2022-MOBO04

About •

Received ※ 15 December 2022 — Revised ※ 14 February 2023 — Accepted ※ 17 February 2023 — Issue date ※ 18 April 2023

Cite •

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

MOPO004

Beam Dump Development for High Power Proton and Electron Beam

proton, target, cavity, controls

54

J.Y. Liu, H.R. Cai, M.Z. Hu, G.F. Pan, S. Pei, G.F. Song, L. Wang, Y. Wang, S.M. Wei, Z.G. Yin, S.P. Zhang, T.J. Zhang, X.F. Zhu
CIAE, Beijing, People’s Republic of China

The high-intensity 100 MeV proton cyclotron CYCIAE-100 had provided 52 kW beam to the beam dump in 2018, is planning to upgrade at China Institute of Atomic Energy(CIAE). It is designed to provide a 75~100 MeV, 1 mA proton beam. So, a new beam dump for higher beam power have been developed since 2020. At the same time, a 1:4 scale, RF cavity with Q value up to 42000, is constructed for the engineering feasibility verification of a 2 GeV/6 MW CW FFAG, which is also being considered as a main accelerating cavity of a 100 kW electron accelerator. The electron beam will be rotated and accelerated 7 times by the gradient dipoles and the high Q cavity. The beam dump is designed to also use for the 100kW electron beam. With the same-level beam power of the two accelerators above the content, a beam dump for absorbing two kinds of particle beams according to the characteristics of the modification was designed. The energy deposition of 100MeV proton beam and 5MeV electron beam in the beam dump was investigated by the Monte-Carlo simulation program FLUKA. The beam dump cooling structure was optimizing by ICEM-CFD and fluent, so that the beam dump temperature was controlled less than 100°C, and the maximum temperature on the beam dump is less than 450°C. The beam dump is designed as a cube (450*200*200, unit:mm) with two 2.5°V-type copper pentagon and two flat parts. All the details about the simulation of energy deposition, thermal distribution and structure design will be presented in the paper.

Poster MOPO004 [3.428 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-CYCLOTRONS2022-MOPO004

About •

Received ※ 31 December 2022 — Revised ※ 26 January 2023 — Accepted ※ 09 February 2023 — Issue date ※ 25 June 2023

Cite •

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

MOPO011

Design and Operation of the New Fast Beam Chopper between Tandetron and Cyclotron

controls, power-supply, electronics, vacuum

76

T. Fanselow, J. Bundesmann, A. Denker, A. Dittwald, U. Hiller
HZB, Berlin, Germany

In collaboration with Charite - Universitätsmedizin Berlin, patients with ocular melanomas are treated with protons at Helmholtz Zentrum Berlin. Accompanying research includes beam delivery for Flash irradiation, thus it became necessary to set up a fast and reliable beam chopper. The new beam chopper can deliver much shorter pulses than needed for Flash irradiation, minimum pulse widths down to 70ns at 1kV amplitude can be delivered. A short description of the design and installation process, which occurred in 2020, and the experiences of the first 2 years of operation with the new fast beam chopper system is presented.

Poster MOPO011 [3.738 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-CYCLOTRONS2022-MOPO011

About •

Received ※ 30 December 2022 — Revised ※ 12 January 2023 — Accepted ※ 01 February 2023 — Issue date ※ 04 July 2023

Cite •

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

MOPO012

An Embedded Beam Diagnostic Electronics for 230 MeV Superconducting Cyclotron Radial Probe and Scanning Wires

electronics, cyclotron, diagnostics, embedded

80

T.Y. Jiang, P. Liu, X. Mu, Q.Q. Song, Y. Wang, Z.G. Yin, T.J. Zhang
CIAE, Beijing, People’s Republic of China

For the 230MeV superconducting cyclotron, once again, the differential radial probe has been proven to be crucial for the beam commission procedure. It can provide various information about the particles inside the cyclotron, such as the vertical position, the relative intensity as well as the oscillation frequency and radius, etc. In practice, however, the electronics system suffered from the leaking alternating RF field as well as the static magnetic field. Besides the EM shielding, an absorptive high-frequency filter has been included as the first element of the readout electronics. A high dynamic range readout electronic unit has been included to adapt to the fluctuation of the beam in the hole commissioning phase. The electronics box is designed as a network-attached embedded device so that it can be powered by a POE switch and transmits measurement results via MODBUS protocol. A dedicated digital signal processor and calibration units are also included, together with the ADCs, to facilitate the daily calibration process. The same electronics are used for the beamline wire scan system to determine the position of the beam, with a small improvement at a lower range. The design of this multi-purpose beam diagnostics electronics will be reviewed in this paper, together with several measurement results.
zhiguoyin@ciae.ac.cn

Poster MOPO012 [0.721 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-CYCLOTRONS2022-MOPO012

About •

Received ※ 01 January 2023 — Revised ※ 27 January 2023 — Accepted ※ 09 February 2023 — Issue date ※ 27 April 2023

Cite •

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

WEPO008

H^- Intra-Beam Stripping Loss Rate in Isochronous Cyclotron

cyclotron, linac, resonance, target

219

Y.-N. Rao
TRIUMF, Vancouver, Canada

Funding: This work was funded by TRIUMF which receives federal funding via a contribution agreement with the National Research Council of Canada.
Binary collisions inside a H^- bunch result in H^- stripping and subsequent particle loss. This phenomenon, called intra-beam stripping, was observed in LEAR and SNS superconducting linac. We mimic the derivation made for the linac to derive the intra-beam stripping loss rate for an isochronous cyclotron. And then, we apply this theory to the TRIUMF 500 MeV H^- cyclotron to estimate the loss.

Poster WEPO008 [1.189 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-CYCLOTRONS2022-WEPO008

About •

Received ※ 05 December 2022 — Revised ※ 04 February 2023 — Accepted ※ 07 February 2023 — Issue date ※ 14 July 2023

Cite •

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

WEPO016

A New 18 GHz ECR Ion Source for Cyclotron at CIAE

ion-source, ECR, cyclotron, injection

234

B. Tang, L.H. Chen, B.Q. Cui, G. Guo, R. Ma, Y.J. Ma, L. Sui, Y.F. Wang, L. Zhang
CIAE, Beijing, People’s Republic of China
Z.H. Jia, L.B. Li, Y.T. Li, W. Lu, J.D. Ma, P. Peng, C. Qian, L.T. Sun, P. Zhang, X.Z. Zhang
IMP/CAS, Lanzhou, People’s Republic of China

In order to meet the requirements of ion beam for the single event effect experiment, the ion source needs to supply ion beams of N, Ne, Si, Ar, Fe, Kr, Xe, and so on for the cyclotron. The most effective way to increase the energy of the cyclotron is to increase the charged state, and the Kr ion charge state reaches +22 while the Xe ion charge state reaches +35. A new room-temperature Electron Cyclotron Resonance (ECR) ion source operating at 18 GHz has been developed and assembled at CIAE. This new ECR ion source is based on the Lanzhou Electron Cyclotron Resonance ion source No.5 (LECR5) developed at IMP. The magnetic confinement of the new ECR ion source is realized by the axial mirror field provided by two set of room temperature pancake coils while the radial hexapole field is supplied by a permanent magnet hexapole. A multi-sputter disk injection component was designed for the production of metallic cocktail ion beams. This paper will give the detailed design of this ion source, and some preliminary highly charged ion beam production results will also be presented.

Poster WEPO016 [0.654 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-CYCLOTRONS2022-WEPO016

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Received ※ 11 February 2023 — Revised ※ 13 February 2023 — Accepted ※ 20 February 2023 — Issue date ※ 01 July 2023

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WEPO017

A New Design of CYCIAE230 Superconducting Cyclotron RF-Driven System

cyclotron, cavity, coupling, resonance

237

Z.G. Yin, X.L. Fu, B. Ji, X. Mu, S. Pei, J.Y. Wei, T.J. Zhang
CIAE, Beijing, People’s Republic of China

A superconducting cyclotron with a beam energy of 246.2MeV has been developed and commissioned by the China Institute of Atomic Energy. The RF system of the first CYCIAE-230 cyclotron adopts two tetrode amplifiers to drive the cavities simultaneously. The driven power is 180 degrees out of phase and each of the amplifiers was designed able to deliver 75kW RF power to the cavities. In practice, it was found that the driven power is beyond necessary and only 80kW RF power is required for the beam. Hence, an upgrade of the existing RF-driven system to the stare-of-art of solid-state technology is put forward by the CIAE cyclotron team. Furthermore, this alternative design also includes an optimization of the coupling between amplifiers and the cavities, since the old coupler shows nonidealities under long-term high-power operations. A driven schema utilizing multiple low-power capacitive couplers is designed to address this issue, taking advantage of the cavity as a power combiner. In this paper, a review of the existing RF-driven system will be given first. It will be followed by an analysis of the limitation of such a system in practice. A new design of the solid amplifier, the new driven method, and a capacitive window will also be reported.

DOI •

reference for this paper ※ doi:10.18429/JACoW-CYCLOTRONS2022-WEPO017

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Received ※ 25 December 2022 — Revised ※ 29 January 2023 — Accepted ※ 09 February 2023 — Issue date ※ 02 June 2023

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WEPO018

Progress in the Design of a New 150-MHz Flat Top Cavity for the PSI RING Cyclotron

cavity, cyclotron, flattop, multipactoring

241

J.-Y. Raguin, M. Bopp, R.F. Fortunati, J. Grillenberger, T.G. Lucas, M. Pedrozzi, M. Schneider, M. Stoll
PSI, Villigen PSI, Switzerland
E. Solodko
Transmutex SA, Vernier, Switzerland

Increasing PSI’s 590 MeV main cyclotron beam current to 3 mA requires the replacement of the existing power-limited 150 MHz flat top cavity with a new cavity. This new cavity has been designed to withstand a 700 kV peak voltage and a 140 kW dissipated average power. Although very similar in its geometry to the original flat top cavity currently in operation, in the new design, special attention has been paid to the shaping of the four electrodes for maximizing the shunt impedance. Furthermore, the topology of the cooling water channels has been optimized to increase the power handling capabilities of the cavity. Finally, in order to mitigate multipacting observed in the current design, variations on the new cavity baseline geometry have started to be explored.

Poster WEPO018 [4.072 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-CYCLOTRONS2022-WEPO018

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Received ※ 30 November 2022 — Revised ※ 13 January 2023 — Accepted ※ 01 February 2023 — Issue date ※ 12 March 2023

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THPO002

Study on Proton Radiation Effect and Self-Repair of SiC-JBS Diodes

radiation, proton, ECR, interface

291

C.C. Liu, Q. Chen, G. Guo, H.L. Shi, F.Q. Zhang, z. Zhang
CIAE, Beijing, People’s Republic of China

Funding: CNNC "Young Talents" Scientific Research Project (11FY212306000801)
In this study, the influence of proton irradiation experiments at 40 MeV and p/cm² on Silicon Carbide Junction Barrier Schottky (SiC-JBS) diodes with stripe cell and hexagonal cell designs was investigated, respectively. Considering the displacement damage effect of SiC-JBS diodes, the experiments was implemented on unbiased SiC-JBS diodes based on 100 MeV high intensity proton cyclotron of China Institute of Atomic Energy. The results show that the current voltage (IV) and capacitive voltage (CV) characteristics of the SiC-JBS diodes are obviously degraded by proton irradiation. After 168 h of room temperature annealing, the forward IV characteristics of the SiC-JBS diodes are basically restored but the reverse leakage current is increased. After 336 h of room temperature annealing, the forward IV characteristic of the diodes is completely restored, but the reserve IV characteristic of the diodes with stripe cell is completely restored. And the CV characteristic is degraded of the two kinds of SiC-JBS diodes permanently, which indicating that room temperature annealing cannot restore the proton radiation displacement damage defects. Combined with Monte Carlo simulations, it is shown that proton irradiation will introduce ionization defects and displacement defects into the SiC-JBS diodes, in which the disappearance of displacement damage defects will eventually lead to the degradation of electrical properties of reverse IV and CV. The analysis of the SiC-JBS diodes structure shows that, without considering the diode materials and process level, the SiC-JBS diode with hexagonal cells is more resistant to proton irradiation displacement damage and has stronger room temperature annealing self-repair ability than the SiC-JBS diodes with stripe cells, even though its chip area is smaller. On the other hand, the SiC-JBS diodes with hexagonal cells can be used preferentially in the radiation environment where there is a large amount of proton.

Poster THPO002 [5.018 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-CYCLOTRONS2022-THPO002

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Received ※ 21 December 2022 — Revised ※ 21 January 2023 — Accepted ※ 14 March 2023 — Issue date ※ 14 April 2023

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THPO003

Applications of the CYCIAE-100 Cyclotron in Neutron-Induced Single Event Effect

neutron, proton, radiation, target

295

Q. Chen, J. Bao, G. Guo, J.H. Han, X. Ma, H.Y. Zhao
CIAE, Beijing, People’s Republic of China

Neutron-induced single event effect is one of the significant factors affecting the reliability of semiconductor devices in avionics and ground facilities. The 100 MeV proton cyclotron in China Institute of Atomic Energy (Cyciae-100) provides white neutron and quasi-monoenergetic neutron induced by proton and W/Li bombardment. Based on the white neutron beam line of Cyciae-100, the white neutron energy spectrum is measured by neutron time-of-flight method with double scintillator spectrometer, as well as the theoretical energy spectrum calculated by the Monte Carlo method. The neutron irradiation test of two SRAMs with different technology nodes were carried out, and the neutron single event upset sections are obtained simultaneously. In addition, based on the quasi-monoenergetic neutron beam line, the simulation of neutron energy spectrum and experimental measurement of neutron single event upset cross section for SRAMs were carried out. As a conclusion, the white neutron and quasi-monoenergetic neutron provided by Cyciae-100 are well suitable applied to the study of neutron single event effects.

Poster THPO003 [0.726 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-CYCLOTRONS2022-THPO003

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Received ※ 31 December 2022 — Revised ※ 21 January 2023 — Accepted ※ 31 January 2023 — Issue date ※ 02 April 2023

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THPO008

Consideration of Using Non-Destructive Detectors in the Beamline of a Proton Therapy Facility

proton, cyclotron, detector, cavity

314

Q.S. Chen, A.T. Chen, B. Qin
HUST, Wuhan, People’s Republic of China

Funding: This work is supported by the National Science Foundation of China under the contract No. 12175077.
Ionization profile monitors (IPM) are a kind of nondestructive monitors mostly used in accelerators of high intensity pulsed beams. As for particle therapy accelerators, either based on cyclotrons or synchrotrons, the extracted beams are very weak, usually on the level of nano-Amperes. Up to date, the commonly used detectors in such low current machines are all destructive, such as fluorescent screens and gas ionization chambers. In this paper, we proposed for the first time to use a residual gas ionization monitor to measure the beam profiles in a proton therapy facility based on a superconducting cyclotron. The feasibility of such a scheme and some basic issues are discussed in this paper.

Poster THPO008 [0.535 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-CYCLOTRONS2022-THPO008

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Received ※ 30 December 2022 — Revised ※ 13 February 2023 — Accepted ※ 19 February 2023 — Issue date ※ 07 June 2023

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