IPAC2021 - List of Authors (Tang, J.Y.)

Paper	Title	Page
TUPAB362	Physical Design of Electrostatic Deflector in CSNS Muon Source	2360
	Y.W. Wu, S. Li, J.Y. Tang, X. Wu IHEP, Beijing, People’s Republic of China C.D. Deng, Y. Hong DNSC, Dongguan, People’s Republic of China Y.Q. Liu IHEP CSNS, Guangdong Province, People’s Republic of China
	CSNS will build a muon source at the end of the RTBT. In the current design, the muon source propose two schemes, namely the baseline scheme and the baby scheme. High voltage electrostatic deflectors (ESD) are used to deflect the beam in the two schemes. A three-channel ESD with 400 kV HV is employed in the baseline scheme and a 210 kV dual-channel ESD in the simplified scheme. According to physical requirements, the electric field concentration factor is introduced, and the electrode of ESD is theoretically designed. 2D and 3D simulations are carried out to analyze the characteristics of electric field distribution by OPERA. The geometry of the electrodes also met the requirements of electric field uniformity, high voltage resistance and mechanical strength at the same time. In the baseline scheme and the baby scheme, the ESD electric field concentration factors are 1.36 and 1.53, and the maximum electric field is 6.78MV/m and 4.6MV/m, respectively. The design meets the requirements and is reasonably feasible.
	Poster TUPAB362 [2.214 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB362
About •	paper received ※ 13 May 2021 paper accepted ※ 09 June 2021 issue date ※ 22 August 2021
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPAB202	Problem and Solution with the Longitudinal Tracking of the ORBIT Code	4176
	L.H. Zhang, J.Y. Tang IHEP, Beijing, People’s Republic of China Y.K. Chen IHEP CSNS, Guangdong Province, People’s Republic of China L.H. Zhang University of Chinese Academy of Sciences, Beijing, People’s Republic of China
	The ORBIT code has been widely used for beam dynamics simulations including injection and acceleration in high-intensity hadron synchrotrons. When the ORBIT’s 1D longitudinal tracking was employed for the acceleration process in CSNS/RCS, the longitudinal emittance in eV-s was found decreasing substantially during acceleration, though the adiabatic condition is still met during this process. This is against the Liouville theorem that predicts the preservation of the emittance during acceleration. The recent machine study in the accelerator and the simulations with a self-made code demonstrate that the longitudinal emittance is almost invariant, which further indicates that the ORBIT longitudinal tracking might be incorrect. A detailed check-over in the ORBIT code source finds that the longitudinal finite difference equation used in the code is erroneous when applied to an acceleration process. The new code format PyORBIT has the same problem. After the small secondary factor is included in the code, ORBIT can produce results keeping the longitudinal emittance invariant. This paper presents some details about the study.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB202
About •	paper received ※ 14 May 2021 paper accepted ※ 01 July 2021 issue date ※ 21 August 2021
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

Physical Design of Electrostatic Deflector in CSNS Muon Source

2360

Y.W. Wu, S. Li, J.Y. Tang, X. Wu
IHEP, Beijing, People’s Republic of China
C.D. Deng, Y. Hong
DNSC, Dongguan, People’s Republic of China
Y.Q. Liu
IHEP CSNS, Guangdong Province, People’s Republic of China

CSNS will build a muon source at the end of the RTBT. In the current design, the muon source propose two schemes, namely the baseline scheme and the baby scheme. High voltage electrostatic deflectors (ESD) are used to deflect the beam in the two schemes. A three-channel ESD with 400 kV HV is employed in the baseline scheme and a 210 kV dual-channel ESD in the simplified scheme. According to physical requirements, the electric field concentration factor is introduced, and the electrode of ESD is theoretically designed. 2D and 3D simulations are carried out to analyze the characteristics of electric field distribution by OPERA. The geometry of the electrodes also met the requirements of electric field uniformity, high voltage resistance and mechanical strength at the same time. In the baseline scheme and the baby scheme, the ESD electric field concentration factors are 1.36 and 1.53, and the maximum electric field is 6.78MV/m and 4.6MV/m, respectively. The design meets the requirements and is reasonably feasible.

Poster TUPAB362 [2.214 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB362

About •

paper received ※ 13 May 2021 paper accepted ※ 09 June 2021 issue date ※ 22 August 2021

Export •

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

THPAB202

Problem and Solution with the Longitudinal Tracking of the ORBIT Code

4176

L.H. Zhang, J.Y. Tang
IHEP, Beijing, People’s Republic of China
Y.K. Chen
IHEP CSNS, Guangdong Province, People’s Republic of China
L.H. Zhang
University of Chinese Academy of Sciences, Beijing, People’s Republic of China

The ORBIT code has been widely used for beam dynamics simulations including injection and acceleration in high-intensity hadron synchrotrons. When the ORBIT’s 1D longitudinal tracking was employed for the acceleration process in CSNS/RCS, the longitudinal emittance in eV-s was found decreasing substantially during acceleration, though the adiabatic condition is still met during this process. This is against the Liouville theorem that predicts the preservation of the emittance during acceleration. The recent machine study in the accelerator and the simulations with a self-made code demonstrate that the longitudinal emittance is almost invariant, which further indicates that the ORBIT longitudinal tracking might be incorrect. A detailed check-over in the ORBIT code source finds that the longitudinal finite difference equation used in the code is erroneous when applied to an acceleration process. The new code format PyORBIT has the same problem. After the small secondary factor is included in the code, ORBIT can produce results keeping the longitudinal emittance invariant. This paper presents some details about the study.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB202

About •

paper received ※ 14 May 2021 paper accepted ※ 01 July 2021 issue date ※ 21 August 2021

Export •

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