CYCLOTRONS2022 - List of Authors (Zhao, B.H.)

Paper	Title	Page
MOPO001	A Real-Time Controller for Rapid Energy Degrading of the CYCIAE-230 Cyclotron Beam Production System	47
	Q.Q. Song, H.R. Cai, Q.K. Guo, A.L. He, T.Y. Jiang, Y. Wang, Z.G. Yin, T.J. Zhang, B.H. Zhao CIAE, Beijing, People’s Republic of China
	The energy selection system (ESS) plays an important role in a proton therapy system. Usually, it consists of an energy degrader, a set of achromatic bending magnets, an envelope collimator, and a momentum-selecting slit. In CIAE, a dedicated beam transportation line, including these essential elements, for the CYCIAE-230 superconducting cyclotron has been designed and manufactured for study purposes. To reduce the layer switching time, e.g. typically within 50 milliseconds, this ESS system takes advantage of VME-based real-time controller design. On one side, this controller uses S-curve to direct drive the step motors of various actuators, this is done by an off-the-shelf embedded controller. On the other hand, it uses Data Distribution Service (DDS) communication protocol to tap into the nozzle control system network directly. In such a manner, the energy requirement can be efficiently handled and the controller is also responsible for the current regulation of the 46 magnets. The design of this high-efficiency controller will be reported in this paper, both from hardware and software aspects. Preliminary test results will also be evaluated and analyzed to direct further improvement of the system.
DOI •	reference for this paper ※ doi:10.18429/JACoW-CYCLOTRONS2022-MOPO001
About •	Received ※ 20 October 2022 — Revised ※ 27 January 2023 — Accepted ※ 30 January 2023 — Issue date ※ 10 July 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPO008	PLC Based Vacuum Control and Interlock System of the CYCIAE-230 Superconducting Cyclotron Beam Line	70
	M.Z. Hu, H.R. Cai, A.L. He, S.M. Jiang, T.Y. Jiang, J.Y. Liu, P. Liu, Q.Q. Song, Y. Wang, F.D. Yang, Z.G. Yin, T.J. Zhang, B.H. Zhao, X.F. Zhu CIAE, Beijing, People’s Republic of China
	In the CYCIAE-230 superconducting cyclotron beam line, a vacuum system capable of providing a pressure of about 5·10^-4 Pa is required for particle beam transport. In order to provide adequate interlocking to safeguard the vacuum environment and ensure the regular transmission of particles within the beam line, a vacuum control system based on programmable logic controller (PLC) has been developed and integrated into the accelerator monitoring system. The PLC not only interfaces with the quick-acting relay based on interlocking signals but also interfaces with the equipment based on Profibus communication to monitor and control various parameters in the vacuum system, such as pump speed, vacuum pressure reading, valve status, water cooling status, etc. This work presents the structure and interface logic necessary for communication with a series of valves, vacuum gauges, and molecular pump controllers. Also presented is an interface approach between vacuum control and the rest of the accelerator control system.
	Poster MOPO008 [3.051 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-CYCLOTRONS2022-MOPO008
About •	Received ※ 27 December 2022 — Revised ※ 26 January 2023 — Accepted ※ 09 February 2023 — Issue date ※ 01 April 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPO019	Optimization of Rapid Magnetic Field Control of the CYCIAE-230 Cyclotron Beamline Magnets	106
	A.L. He, H.R. Cai, Q.K. Guo, P. Huang, Q.Q. Song, Y. Wang, Z.G. Yin, T.J. Zhang, B.H. Zhao CIAE, Beijing, People’s Republic of China
	The magnetic field precise and rapid control of the beamline magnets is essential to the Energy Selection System (ESS) for the proton therapy facility. During the scanning of proton beam for therapy, the field of each beamline magnet should be precisely controlled within the set time, layer upon layer. The position of beam spot to the nozzle should undoubtedly be stable and unchanged during the process. In practice, however, due to the wide energy range of proton therapy (70 MeV-230 MeV), the dynamic response of the beamline magnets usually shows nonlinear performances at a different energy, e.g., the magnetic field may cause a significant overshoot for some specific beam energy if one ignores the nonlinear effect. More challenge is that the magnetic field drops too slowly between the energy steps, which compromises the overall performance of rapid intensity modulated scanning therapy. A dynamic PID parameter optimization method is reported in this paper to address this issue. According to the transfer function of each magnet, the entire energy range is divided into several steps. Then, the experiments are carried out to find the most suitable PID parameters for each energy step. Finally, the "beam energy - excitation current-PID parameters" lookup table (LUT) is generated and stored in the beamline control system BCS for automation. During the treatment, using the LUT allows the energy setting for beamline magnets to be adjusted automatically with the most appropriate PID parameter, guaranteeing the overall performance of rapid scanning therapy. The experimental results show the overall response time of all the beamline magnets reduced from several hundred milliseconds to less than 65 ms, which meets the design requirement of less than 80ms.
	Poster MOPO019 [0.364 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-CYCLOTRONS2022-MOPO019
About •	Received ※ 06 January 2023 — Revised ※ 30 January 2023 — Accepted ※ 01 February 2023 — Issue date ※ 10 February 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THAI01	Recent Progress of Research and Development for the Cost-Effective, Energy-Efficient Proton Accelerator CYCIAE-2000	245
	T.J. Zhang, H.R. Cai, Z.C. Chu, W.F. Fu, A.L. He, M.Z. Hu, X.L. Jia, Z.J. Jin, H. Le, J. Lin, J.Y. Liu, X. Mu, G.F. Pan, S. Pei, Q.Q. Song, C. Wang, F. Wang, Y. Wang, Z.G. Yin, Z.Y. Yin, S.P. Zhang, B.H. Zhao, H. Zhou, X.F. Zhu CIAE, Beijing, People’s Republic of China
	Funding: This work was supported in part by the National Natural Science Foundation of China under Grant 12135020 and the basic research fund from the Ministry of Finance of China under Grant BRF201901. The MW class proton accelerators are expected to play important role in many fields, attracting institutions to continue research and tackle key problems. The CW isochronous accelerator obtains a high power beam with higher energy efficiency, which is very attractive to many applications. Scholars generally believe that the energy limitation of the isochronous cyclotron is ~1 GeV. To get higher beam power by the isochronous machine, enhancing the beam focusing become the most important issue. Adjusting the radial gradient of the average magnetic field makes the field distribution match the isochronism. When we adjust the radial gradient of the peak field, the first-order gradient is equivalent to the quadrupole field, the second-order, the hexapole field, and so on. Just like the synchrotron, there are quadrupoles, hexapole magnets, and so on, along the orbits to get higher energy, as all we know. If we adjust the radial gradient for the peak field of an FFAG’s FDF lattice and cooperate with the angular width (azimuth flutter) and spiral angle (edge focusing) of the traditional cyclotron pole, we can manipulate the working path in the tune diagram very flexibly. During enhancing the axial focusing, both the beam intensity and the energy of the isochronous accelerator are significantly increased. And a 2 GeV CW FFAG with 3 mA of average beam intensity is designed. It is essentially an isochronous cyclotron although we use 10 folders of FDF lattices. The key difficulty is that the magnetic field and each order of gradient should be accurately adjusted in a large radius range. As a high-power proton accelerator with high energy efficiency, we adopt high-temperature superconducting technology for the magnets. 15 RF cavities with a Q value of 90000 provide energy gain per turn of ~15 MeV to ensure the CW beam intensity reaches 3 mA. A 1:4 scale, 15 ton HTS magnet, and a 1:4 scale, 177 MHz cavity have been completed. The results of such R&D will also be presented in this
DOI •	reference for this paper ※ doi:10.18429/JACoW-CYCLOTRONS2022-THAI01
About •	Received ※ 20 January 2023 — Revised ※ 24 January 2023 — Accepted ※ 09 February 2023 — Issue date ※ 04 April 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

A Real-Time Controller for Rapid Energy Degrading of the CYCIAE-230 Cyclotron Beam Production System

47

Q.Q. Song, H.R. Cai, Q.K. Guo, A.L. He, T.Y. Jiang, Y. Wang, Z.G. Yin, T.J. Zhang, B.H. Zhao
CIAE, Beijing, People’s Republic of China

The energy selection system (ESS) plays an important role in a proton therapy system. Usually, it consists of an energy degrader, a set of achromatic bending magnets, an envelope collimator, and a momentum-selecting slit. In CIAE, a dedicated beam transportation line, including these essential elements, for the CYCIAE-230 superconducting cyclotron has been designed and manufactured for study purposes. To reduce the layer switching time, e.g. typically within 50 milliseconds, this ESS system takes advantage of VME-based real-time controller design. On one side, this controller uses S-curve to direct drive the step motors of various actuators, this is done by an off-the-shelf embedded controller. On the other hand, it uses Data Distribution Service (DDS) communication protocol to tap into the nozzle control system network directly. In such a manner, the energy requirement can be efficiently handled and the controller is also responsible for the current regulation of the 46 magnets. The design of this high-efficiency controller will be reported in this paper, both from hardware and software aspects. Preliminary test results will also be evaluated and analyzed to direct further improvement of the system.

DOI •

reference for this paper ※ doi:10.18429/JACoW-CYCLOTRONS2022-MOPO001

About •

Received ※ 20 October 2022 — Revised ※ 27 January 2023 — Accepted ※ 30 January 2023 — Issue date ※ 10 July 2023

Cite •

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

MOPO008

PLC Based Vacuum Control and Interlock System of the CYCIAE-230 Superconducting Cyclotron Beam Line

70

M.Z. Hu, H.R. Cai, A.L. He, S.M. Jiang, T.Y. Jiang, J.Y. Liu, P. Liu, Q.Q. Song, Y. Wang, F.D. Yang, Z.G. Yin, T.J. Zhang, B.H. Zhao, X.F. Zhu
CIAE, Beijing, People’s Republic of China

In the CYCIAE-230 superconducting cyclotron beam line, a vacuum system capable of providing a pressure of about 5·10^-4 Pa is required for particle beam transport. In order to provide adequate interlocking to safeguard the vacuum environment and ensure the regular transmission of particles within the beam line, a vacuum control system based on programmable logic controller (PLC) has been developed and integrated into the accelerator monitoring system. The PLC not only interfaces with the quick-acting relay based on interlocking signals but also interfaces with the equipment based on Profibus communication to monitor and control various parameters in the vacuum system, such as pump speed, vacuum pressure reading, valve status, water cooling status, etc. This work presents the structure and interface logic necessary for communication with a series of valves, vacuum gauges, and molecular pump controllers. Also presented is an interface approach between vacuum control and the rest of the accelerator control system.

Poster MOPO008 [3.051 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-CYCLOTRONS2022-MOPO008

About •

Received ※ 27 December 2022 — Revised ※ 26 January 2023 — Accepted ※ 09 February 2023 — Issue date ※ 01 April 2023

Cite •

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

MOPO019

Optimization of Rapid Magnetic Field Control of the CYCIAE-230 Cyclotron Beamline Magnets

106

A.L. He, H.R. Cai, Q.K. Guo, P. Huang, Q.Q. Song, Y. Wang, Z.G. Yin, T.J. Zhang, B.H. Zhao
CIAE, Beijing, People’s Republic of China

The magnetic field precise and rapid control of the beamline magnets is essential to the Energy Selection System (ESS) for the proton therapy facility. During the scanning of proton beam for therapy, the field of each beamline magnet should be precisely controlled within the set time, layer upon layer. The position of beam spot to the nozzle should undoubtedly be stable and unchanged during the process. In practice, however, due to the wide energy range of proton therapy (70 MeV-230 MeV), the dynamic response of the beamline magnets usually shows nonlinear performances at a different energy, e.g., the magnetic field may cause a significant overshoot for some specific beam energy if one ignores the nonlinear effect. More challenge is that the magnetic field drops too slowly between the energy steps, which compromises the overall performance of rapid intensity modulated scanning therapy. A dynamic PID parameter optimization method is reported in this paper to address this issue. According to the transfer function of each magnet, the entire energy range is divided into several steps. Then, the experiments are carried out to find the most suitable PID parameters for each energy step. Finally, the "beam energy - excitation current-PID parameters" lookup table (LUT) is generated and stored in the beamline control system BCS for automation. During the treatment, using the LUT allows the energy setting for beamline magnets to be adjusted automatically with the most appropriate PID parameter, guaranteeing the overall performance of rapid scanning therapy. The experimental results show the overall response time of all the beamline magnets reduced from several hundred milliseconds to less than 65 ms, which meets the design requirement of less than 80ms.

Poster MOPO019 [0.364 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-CYCLOTRONS2022-MOPO019

About •

Received ※ 06 January 2023 — Revised ※ 30 January 2023 — Accepted ※ 01 February 2023 — Issue date ※ 10 February 2023

Cite •

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

THAI01

Recent Progress of Research and Development for the Cost-Effective, Energy-Efficient Proton Accelerator CYCIAE-2000

245

T.J. Zhang, H.R. Cai, Z.C. Chu, W.F. Fu, A.L. He, M.Z. Hu, X.L. Jia, Z.J. Jin, H. Le, J. Lin, J.Y. Liu, X. Mu, G.F. Pan, S. Pei, Q.Q. Song, C. Wang, F. Wang, Y. Wang, Z.G. Yin, Z.Y. Yin, S.P. Zhang, B.H. Zhao, H. Zhou, X.F. Zhu
CIAE, Beijing, People’s Republic of China

Funding: This work was supported in part by the National Natural Science Foundation of China under Grant 12135020 and the basic research fund from the Ministry of Finance of China under Grant BRF201901.
The MW class proton accelerators are expected to play important role in many fields, attracting institutions to continue research and tackle key problems. The CW isochronous accelerator obtains a high power beam with higher energy efficiency, which is very attractive to many applications. Scholars generally believe that the energy limitation of the isochronous cyclotron is ~1 GeV. To get higher beam power by the isochronous machine, enhancing the beam focusing become the most important issue. Adjusting the radial gradient of the average magnetic field makes the field distribution match the isochronism. When we adjust the radial gradient of the peak field, the first-order gradient is equivalent to the quadrupole field, the second-order, the hexapole field, and so on. Just like the synchrotron, there are quadrupoles, hexapole magnets, and so on, along the orbits to get higher energy, as all we know. If we adjust the radial gradient for the peak field of an FFAG’s FDF lattice and cooperate with the angular width (azimuth flutter) and spiral angle (edge focusing) of the traditional cyclotron pole, we can manipulate the working path in the tune diagram very flexibly. During enhancing the axial focusing, both the beam intensity and the energy of the isochronous accelerator are significantly increased. And a 2 GeV CW FFAG with 3 mA of average beam intensity is designed. It is essentially an isochronous cyclotron although we use 10 folders of FDF lattices. The key difficulty is that the magnetic field and each order of gradient should be accurately adjusted in a large radius range. As a high-power proton accelerator with high energy efficiency, we adopt high-temperature superconducting technology for the magnets. 15 RF cavities with a Q value of 90000 provide energy gain per turn of ~15 MeV to ensure the CW beam intensity reaches 3 mA. A 1:4 scale, 15 ton HTS magnet, and a 1:4 scale, 177 MHz cavity have been completed. The results of such R&D will also be presented in this

DOI •

reference for this paper ※ doi:10.18429/JACoW-CYCLOTRONS2022-THAI01

About •

Received ※ 20 January 2023 — Revised ※ 24 January 2023 — Accepted ※ 09 February 2023 — Issue date ※ 04 April 2023

Cite •

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