IPAC2021 - List of Authors (Li, M.T.)

Paper	Title	Page
TUPAB195	Local Orbit Correction Application for CSNS-RCS High Intensity Commissioning	1865
	Y.W. An, Y. Li, S.Y. Xu, Y. Yuan IHEP, Beijing, People’s Republic of China M.T. Li IHEP CSNS, Guangdong Province, People’s Republic of China
	The China Spallation Neutron Source (CSNS) is a high intensity hadron pulse facility which achieved the design goal in March, 2020. The Rapid Cycling Synchrotron (RCS) is the important part of the CSNS which accelerates the proton beam from 80MeV to 1.6GeV. During the high intensity commissioning of the RCS, an local orbit correction application was developed. Because of the good performance of the local orbit controlling at the ramping stage, the beam loss was optimized effectively in the process of the acceleration. In the paper, the efficiency of the beam loss optimization during the acceleration is given and the future plans were proposed.
	Poster TUPAB195 [2.279 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB195
About •	paper received ※ 13 May 2021 paper accepted ※ 17 June 2021 issue date ※ 01 September 2021
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TUPAB263	The Phase Loop Status of the RF System in CSNS/RCS	2076
	L. Huang, X. Li, S. Wang IHEP, Beijing, People’s Republic of China M.T. Li, H.Y. Liu IHEP CSNS, Guangdong Province, People’s Republic of China Y. Liu DNSC, Dongguan, People’s Republic of China
	The Rapid Cycling Synchrotron (RCS) of the China Spallation Neutron Source (CSNS) is a high intensity proton accelerator. The acceleration system consists of eight ferrite loaded cavities. The RCS is the space charge dominant machine and it is mitigated through the bunch factor optimization in the beam commissioning, so the injected beam will occupy a larger bucket size and unavoidable mismatch with the bucket, thus the dipole oscillation is excited. The phase loop scheme is designed to restrict the oscillation in the RF system, but the transmission efficiency is reduced by the phase loop and the bunch factor also increases, so the phase loop scheme is studied. To keep the phase loop but also maintain the transmission efficiency, we optimized the original phase loop scheme, but the beam loss still increases small when the loop on.
	Poster TUPAB263 [1.548 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB263
About •	paper received ※ 13 May 2021 paper accepted ※ 02 June 2021 issue date ※ 21 August 2021
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THPAB185	Solution to Beam Transmission Decline in the CSNS Linac Operation Using Measurements and Simulations	4134
	J. Peng, M.T. Li, X.H. Lu, X.B. Luo IHEP CSNS, Guangdong Province, People’s Republic of China Y.W. An, S. Fu, L. Huang, M.Y. Huang, Y. Li, Z.P. Li, S. Wang, S.Y. Xu, Y. Yuan IHEP, Beijing, People’s Republic of China
	The CSNS linac operation at its design average power currently. However, the beam transmission is declining and the beam loss is increasing during the operation. With simulations and experiments, we found there is a long longitudinal tail exist in the beam bunch output from the RFQ. And this tail caused the beam loss in the following linac. After inhibition of the longitudinal tail in the beam bunch, the beam transmission in operation can keep stable.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB185
About •	paper received ※ 19 May 2021 paper accepted ※ 01 July 2021 issue date ※ 02 September 2021
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THPAB207	Beam Dynamics Simulation about the Dual Harmonic System by PyORBIT	4194
	H.Y. Liu, X.Y. Feng, L. Huang, M.T. Li, X.H. Lu IHEP CSNS, Guangdong Province, People’s Republic of China S. Wang, S.Y. Xu IHEP, Beijing, People’s Republic of China
	The space charge effect is a strong limitation in high-intensity accelerators, especially for low- and medium-energy proton synchrotrons. And for CSNS-II, the number of particles in the RCS is 3.9·10¹³ ppp, which is five times of CSNS. To mitigate the effects of the strong space charge effect, CSNS-II/RCS (Rapid Cycling Synchrotron) will use a dual harmonic system to increase the bunching factor during the injection and the initial acceleration phase. For studying the beam dynamics involved in a dual harmonic RF system, PyORBIT is used as the major simulation code, which is developed at SNS to simulate beam dynamics in accumulation rings and synchrotrons. We modified parts of the code to make it applicable to the beam dynamic in RCS. This paper includes the major code modification of the Dual Harmonic RF system and some benchmark results. The preliminary simulation results of the dual-harmonic system in CSNS-II/RCS simulated by the particle tracking code PyORBIT will also be discussed.
	Poster THPAB207 [0.354 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB207
About •	paper received ※ 16 May 2021 paper accepted ※ 05 July 2021 issue date ※ 11 August 2021
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

Local Orbit Correction Application for CSNS-RCS High Intensity Commissioning

1865

Y.W. An, Y. Li, S.Y. Xu, Y. Yuan
IHEP, Beijing, People’s Republic of China
M.T. Li
IHEP CSNS, Guangdong Province, People’s Republic of China

The China Spallation Neutron Source (CSNS) is a high intensity hadron pulse facility which achieved the design goal in March, 2020. The Rapid Cycling Synchrotron (RCS) is the important part of the CSNS which accelerates the proton beam from 80MeV to 1.6GeV. During the high intensity commissioning of the RCS, an local orbit correction application was developed. Because of the good performance of the local orbit controlling at the ramping stage, the beam loss was optimized effectively in the process of the acceleration. In the paper, the efficiency of the beam loss optimization during the acceleration is given and the future plans were proposed.

Poster TUPAB195 [2.279 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB195

About •

paper received ※ 13 May 2021 paper accepted ※ 17 June 2021 issue date ※ 01 September 2021

Export •

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

TUPAB263

The Phase Loop Status of the RF System in CSNS/RCS

2076

L. Huang, X. Li, S. Wang
IHEP, Beijing, People’s Republic of China
M.T. Li, H.Y. Liu
IHEP CSNS, Guangdong Province, People’s Republic of China
Y. Liu
DNSC, Dongguan, People’s Republic of China

The Rapid Cycling Synchrotron (RCS) of the China Spallation Neutron Source (CSNS) is a high intensity proton accelerator. The acceleration system consists of eight ferrite loaded cavities. The RCS is the space charge dominant machine and it is mitigated through the bunch factor optimization in the beam commissioning, so the injected beam will occupy a larger bucket size and unavoidable mismatch with the bucket, thus the dipole oscillation is excited. The phase loop scheme is designed to restrict the oscillation in the RF system, but the transmission efficiency is reduced by the phase loop and the bunch factor also increases, so the phase loop scheme is studied. To keep the phase loop but also maintain the transmission efficiency, we optimized the original phase loop scheme, but the beam loss still increases small when the loop on.

Poster TUPAB263 [1.548 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB263

About •

paper received ※ 13 May 2021 paper accepted ※ 02 June 2021 issue date ※ 21 August 2021

Export •

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

THPAB185

Solution to Beam Transmission Decline in the CSNS Linac Operation Using Measurements and Simulations

4134

J. Peng, M.T. Li, X.H. Lu, X.B. Luo
IHEP CSNS, Guangdong Province, People’s Republic of China
Y.W. An, S. Fu, L. Huang, M.Y. Huang, Y. Li, Z.P. Li, S. Wang, S.Y. Xu, Y. Yuan
IHEP, Beijing, People’s Republic of China

The CSNS linac operation at its design average power currently. However, the beam transmission is declining and the beam loss is increasing during the operation. With simulations and experiments, we found there is a long longitudinal tail exist in the beam bunch output from the RFQ. And this tail caused the beam loss in the following linac. After inhibition of the longitudinal tail in the beam bunch, the beam transmission in operation can keep stable.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB185

About •

paper received ※ 19 May 2021 paper accepted ※ 01 July 2021 issue date ※ 02 September 2021

Export •

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

THPAB207

Beam Dynamics Simulation about the Dual Harmonic System by PyORBIT

4194

H.Y. Liu, X.Y. Feng, L. Huang, M.T. Li, X.H. Lu
IHEP CSNS, Guangdong Province, People’s Republic of China
S. Wang, S.Y. Xu
IHEP, Beijing, People’s Republic of China

The space charge effect is a strong limitation in high-intensity accelerators, especially for low- and medium-energy proton synchrotrons. And for CSNS-II, the number of particles in the RCS is 3.9·10¹³ ppp, which is five times of CSNS. To mitigate the effects of the strong space charge effect, CSNS-II/RCS (Rapid Cycling Synchrotron) will use a dual harmonic system to increase the bunching factor during the injection and the initial acceleration phase. For studying the beam dynamics involved in a dual harmonic RF system, PyORBIT is used as the major simulation code, which is developed at SNS to simulate beam dynamics in accumulation rings and synchrotrons. We modified parts of the code to make it applicable to the beam dynamic in RCS. This paper includes the major code modification of the Dual Harmonic RF system and some benchmark results. The preliminary simulation results of the dual-harmonic system in CSNS-II/RCS simulated by the particle tracking code PyORBIT will also be discussed.

Poster THPAB207 [0.354 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB207

About •

paper received ※ 16 May 2021 paper accepted ※ 05 July 2021 issue date ※ 11 August 2021

Export •

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