IPAC2016 - List of Authors (Zhang, T.)

Paper	Title	Page
WEPOR058	Preliminary Study for the HLS Variable Pulse Length Storage Ring by Two Harmonic Cavities	2802
SUPSS011	use link to see paper's listing under its alternate paper code
	T. Zhang, W. Li, L. Shang, L. Wang, C.-F. Wu USTC/NSRL, Hefei, Anhui, People's Republic of China
	The 4th harmonic cavity is successfully used in HLS II to increase the beam lifetime and suppress the beam instability now. At the future, a scheme of the two higher harmonic cavities may be applied in Hefei light source for a variable electron pulse length storage ring (HLS VSR). With optimal RF system parameters, 45 ps long bunches and 6 ps short bunches may be stored simultaneously in the HLS storage ring. The ratio of the bunch number for 45 ps to the one for 6 ps is 1:2. Particle tracking calculations are performed to simulate the longitudinal phase space of the new system and to track the process of shortening bunches with Elegant Software. Moreover, a tracking simulation code for RF systems is developed in MALAB to study transient beam loading which affects bunch length, phase stability, and longitudinal muti-bunch oscillation for different fill patterns. In the end, the preliminary design of the two harmonic cavities for longitudinal bunch focusing is given.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPOR058
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WEPOR059	Calculation for the Radiation Dose in Storage Ring Hall based on Monte Carlo Method	2805
	S. Huang, T.L. He, S.C. Zhang, T. Zhang USTC/NSRL, Hefei, Anhui, People's Republic of China
	Radiation dose assessment in synchrotron radiation facility is challenging due to the complexity and uncertainties of radiation source terms induced by high energy particle accelerator. Hefei light source (HLS) is the first dedicated synchrotron radiation light source in China. Radiation dose assessment for users at HLS Beam lines is highly concerned. This study presents the method calculating the radiation dose in storage ring hall under normal operation state, the simplified Monte Carlo calculation model was introduced in detail. We obtained the results of radiation dose distribution in HLS storage ring hall with using MCNP, which are in the same order of magnitude with the experimental results. It indicates that the method can be used to calculate the radiation dose level in storage ring hall, and it has certain guiding significance for the radiation protection.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPOR059
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THPMB024	Error Analysis for the Lattice of FELiChEM	3278
	S. Huang, Z.G. He, W. Xu, S.C. Zhang, T. Zhang USTC/NSRL, Hefei, Anhui, People's Republic of China
	FELiChEM is a new experimental facility under construction at University of Science and Technology of China (USTC).The facility consists of the middle-infrared (MID-FEL) beam line for 2.5-50 um and the Far-infrared (FAR-FEL) beam line for 40-200um. To achieve the design FEL performance of IR-FEL, the beam with 30 mm-mrad emittance, 5 ps rms length and 1nC bunch charge is required. We conduct error analysis in order to evaluate the tolerances of machine parameters and alignments. In this paper, we simulate the orbit corrections and emittance growth under exist of misalignments and strength errors of magnets. The simulation results show that the trajectory errors can be corrected to mm levels in the whole lattice and the emittance increase is acceptable. At the entrance of undulator, the position and angular errors can be corrected very well. So the trajectory can be controlled in the undulator to meet the requirement of FEL.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPMB024
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THPMB025	The Effect of Magnetic Field on the Secondary Electron Yield in the Ultra-High Vacuum Environment	3281
	J. Wang, Y. Wang, W. Wei, Y.H. Xu, B. Zhang, T. Zhang, Y.X. Zhang USTC/NSRL, Hefei, Anhui, People's Republic of China
	A secondary electron emission measurement system has been designed and used to study the secondary electron emission (SEE) of different materials with an independently adjustable energy of 50 eV to 5 keV at National Synchrotron Radiation Laboratory. Here, we obtained the characteristics of the SEE yield from Pd film coatings, under the condition of magnetic field and without magnetic field. Then it was analysed that the effect of magnetic field on the secondary electron yield in the ultra-high vacuum environment. The results show that magnetic field shielding is critical to avoid the influence of magnetic field during secondary electron yield (SEY) measurements.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPMB025
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THPMB026	Research on Low Secondary Electron Yield Materials for Future Accelerators	3284
	J. Wang, Y. Wang, W. Wei, Y.H. Xu, B. Zhang, T. Zhang, Y.X. Zhang USTC/NSRL, Hefei, Anhui, People's Republic of China
	For future accelerators, such as SPPC (SEYmax <1.2), the build-up of electron cloud generated in the beam pipes considerably affect the stability of particle beams. Therefore, it is critical to look for steady and low secondary electron yield (SEY) material for future high intensity accelerators.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPMB026
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Paper

Title

Page

WEPOR058

Preliminary Study for the HLS Variable Pulse Length Storage Ring by Two Harmonic Cavities

2802

SUPSS011

use link to see paper's listing under its alternate paper code

T. Zhang, W. Li, L. Shang, L. Wang, C.-F. Wu
USTC/NSRL, Hefei, Anhui, People's Republic of China

The 4th harmonic cavity is successfully used in HLS II to increase the beam lifetime and suppress the beam instability now. At the future, a scheme of the two higher harmonic cavities may be applied in Hefei light source for a variable electron pulse length storage ring (HLS VSR). With optimal RF system parameters, 45 ps long bunches and 6 ps short bunches may be stored simultaneously in the HLS storage ring. The ratio of the bunch number for 45 ps to the one for 6 ps is 1:2. Particle tracking calculations are performed to simulate the longitudinal phase space of the new system and to track the process of shortening bunches with Elegant Software. Moreover, a tracking simulation code for RF systems is developed in MALAB to study transient beam loading which affects bunch length, phase stability, and longitudinal muti-bunch oscillation for different fill patterns. In the end, the preliminary design of the two harmonic cavities for longitudinal bunch focusing is given.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPOR058

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

WEPOR059

Calculation for the Radiation Dose in Storage Ring Hall based on Monte Carlo Method

2805

S. Huang, T.L. He, S.C. Zhang, T. Zhang
USTC/NSRL, Hefei, Anhui, People's Republic of China

Radiation dose assessment in synchrotron radiation facility is challenging due to the complexity and uncertainties of radiation source terms induced by high energy particle accelerator. Hefei light source (HLS) is the first dedicated synchrotron radiation light source in China. Radiation dose assessment for users at HLS Beam lines is highly concerned. This study presents the method calculating the radiation dose in storage ring hall under normal operation state, the simplified Monte Carlo calculation model was introduced in detail. We obtained the results of radiation dose distribution in HLS storage ring hall with using MCNP, which are in the same order of magnitude with the experimental results. It indicates that the method can be used to calculate the radiation dose level in storage ring hall, and it has certain guiding significance for the radiation protection.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPOR059

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

THPMB024

Error Analysis for the Lattice of FELiChEM

3278

S. Huang, Z.G. He, W. Xu, S.C. Zhang, T. Zhang
USTC/NSRL, Hefei, Anhui, People's Republic of China

FELiChEM is a new experimental facility under construction at University of Science and Technology of China (USTC).The facility consists of the middle-infrared (MID-FEL) beam line for 2.5-50 um and the Far-infrared (FAR-FEL) beam line for 40-200um. To achieve the design FEL performance of IR-FEL, the beam with 30 mm-mrad emittance, 5 ps rms length and 1nC bunch charge is required. We conduct error analysis in order to evaluate the tolerances of machine parameters and alignments. In this paper, we simulate the orbit corrections and emittance growth under exist of misalignments and strength errors of magnets. The simulation results show that the trajectory errors can be corrected to mm levels in the whole lattice and the emittance increase is acceptable. At the entrance of undulator, the position and angular errors can be corrected very well. So the trajectory can be controlled in the undulator to meet the requirement of FEL.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPMB024

Export •

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

THPMB025

The Effect of Magnetic Field on the Secondary Electron Yield in the Ultra-High Vacuum Environment

3281

J. Wang, Y. Wang, W. Wei, Y.H. Xu, B. Zhang, T. Zhang, Y.X. Zhang
USTC/NSRL, Hefei, Anhui, People's Republic of China

A secondary electron emission measurement system has been designed and used to study the secondary electron emission (SEE) of different materials with an independently adjustable energy of 50 eV to 5 keV at National Synchrotron Radiation Laboratory. Here, we obtained the characteristics of the SEE yield from Pd film coatings, under the condition of magnetic field and without magnetic field. Then it was analysed that the effect of magnetic field on the secondary electron yield in the ultra-high vacuum environment. The results show that magnetic field shielding is critical to avoid the influence of magnetic field during secondary electron yield (SEY) measurements.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPMB025

Export •

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

THPMB026

Research on Low Secondary Electron Yield Materials for Future Accelerators

3284

J. Wang, Y. Wang, W. Wei, Y.H. Xu, B. Zhang, T. Zhang, Y.X. Zhang
USTC/NSRL, Hefei, Anhui, People's Republic of China

For future accelerators, such as SPPC (SEYmax <1.2), the build-up of electron cloud generated in the beam pipes considerably affect the stability of particle beams. Therefore, it is critical to look for steady and low secondary electron yield (SEY) material for future high intensity accelerators.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPMB026

Export •

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