IPAC2017 - List of Authors (Xuan, K.)

Paper	Title	Page
MOPAB085	Introduction of Beam Position Monitor System in the HLS II Storage Ring	319
	F.F. Wu, L. Lin, X.Y. Liu, P. Lu, B.G. Sun, L.L. Tang, J.G. Wang, J.H. Wei, K. Xuan, Y.L. Yang, T.Y. Zhou, Z.R. Zhou USTC/NSRL, Hefei, Anhui, People's Republic of China
	Funding: Supported by the National Key Research and Development Program of China (No. 2016YFA0402000) Supported by the National Science Foundation of China (11575181, 11605202) Beam position monitor(BPM) system for the HLS II storage ring were designed in the HLS II upgrade project. This system is composed of BPM, BPM processor embedded with IOC and OPI. Every component of BPM system is introduced in this paper. BPM processors have different modes of data, such as ADC data, turn-by-turn(TBT) data, fast acquirement(FA) data and slow acquirement(SA) data. Different modes of data are used to different applications. Two applications based on SA data of the BPM system, such as BBA for quadrupole magnet center measurement and beam closed orbit feedback, are described in detail. The result of BBA shows that most magnetic centers of quadrupole magnets are in the range of [-1 mm, 1 mm] with respect to BPM electric centers. The result of beam closed orbit feedback shows that beam orbit stability when the closed orbit feedback system is on is far better than that when the closed orbit feedback system is off.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-MOPAB085
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MOPIK085	Linear Optics Calibration at the HLS-II Storage Ring Using Model Independent Analysis	727
	G. Liu, L. Wang, F.F. Wu, K. Xuan USTC/NSRL, Hefei, Anhui, People's Republic of China
	Linear optics are the main lattice parameters characterizing the linear properties of storage rings. Especially for beta function and phase advance, they are the basic lattice functions which must be accurately calibrated to ensure high quality operation of the machine. Model Independent Analysis (MIA), which adopts mathematical statistical methods to extract the effective lattice information of storage rings by directly analyzing the turn-by-turn beam-position-monitor (BPM) measurements, has been applied at HLS-II to calibrate the linear optics model of the storage ring. The measurements of the turn-by-turn BPM data with all of the 32 BPMs are reported in this paper. The calibration results of the beta function using MIA are presented.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-MOPIK085
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MOPIK087	Development of a Tune Knob for the HLS-II Storage Ring	730
	S.W. Wang, J.Y. Li, W.B. Wu, W. Xu, K. Xuan, X. Zhou USTC/NSRL, Hefei, Anhui, People's Republic of China
	A tune knob is a useful tool for lattice setup and machine studies in a storage ring. It is used to adjust the transverse tunes with a small impact on the beam dynamics. A global tune knob is designed for the Hefei Light Source (HLS). In the tune knob, the quadrupoles are grouped into four families and are symmetrically adjusted. Methodical Accelerator Design-X (MAD-X) is used to calculate the coefficients of the tune knob and the Accelerator Toolbox (AT) is used to double check the accuracy of the tune knob. The chromaticity is corrected by the sextupoles in the storage ring. This paper reports preliminary simulation results of the tune knob for HLS. The beta function deviations are also studied.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-MOPIK087
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TUPIK063	The Configurable Software Interlock System for HLS-II	1836
SUSPSIK086	use link to see paper's listing under its alternate paper code
	Y. Song, G. Liu, K. Xuan USTC/NSRL, Hefei, Anhui, People's Republic of China
	The interlock system is an essential component for an accelerator facility. A configurable software interlock system(SIS) is designed for Hefei Light Source II (HLS-II), which complements the hardware interlock system to ensure equipment and operators' safety. The system is developed using Python under the EPICS framework with the method of separating the configuration file from the interlock program. The interlock logic is completely determined by the configuration file and its nested tree structure is easy to expand. The test results indicate that the new software interlock system is reliable, flexible and convenient to operate. This paper will describe the design and the construction of HLS-II SIS.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-TUPIK063
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TUPIK066	Beam Loss Simulation and Radiation Shielding for Top-Off Operation of Hefei Light Source	1845
	X. Zhou, J.Y. Li, J.G. Wang, S.W. Wang, W.B. Wu, W. Xu, K. Xuan, Q.B. Zeng USTC/NSRL, Hefei, Anhui, People's Republic of China
	The Hefei Light Source (HLS) is undergoing a series of upgrades to prepare for the top-off operation. To ensure radiation safety in the experimental hall under abnormal beam loss, simulations under various system errors in the HLS storage ring are performed to get in-depth understanding of the induced radiation nature. To make the radiation shielding more effective, a beam scraper is used to decrease the aperture opening of the vacuum chamber, and additional shielding is installed around the scraper. Simulation and beam test results are reported in this paper.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-TUPIK066
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WEPAB063	Considerations on Developing a Dedicated Terahertz Light Source Based on the HLS-II Storage Ring	2716
	S.W. Wang, J.Y. Li, W.B. Wu, W. Xu, K. Xuan, X. Zhou USTC/NSRL, Hefei, Anhui, People's Republic of China
	There is an increasing interest in generating terahertz radiation for different kinds of researches. A high-power terahertz light source can be realized through coherent synchrotron radiation from a storage ring. The radiation power of coherent synchrotron radiation is proportional to square of the number of electrons in a bunch. To generate coherent synchrotron radiation, the electron bunch length should be shorter than its radiation wavelength. This paper presents our preliminary study on developing a terahertz light source based on Hefei Light Source. We will introduce the status of Hefei Light Source (HLS) and discusses the approach to change it to a dedicated Terahertz light source using coherent synchrotron radiation. Several schemes are proposed to shorten the electron bunch length in the storage ring, including using a low alpha lattice, adopting a magnetic chicane and upgrading the RF system with much higher frequency. The related beam instabilities are also analyzed to predict the beam current threshold.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-WEPAB063
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WEPAB064	Upgrade Project on Top-Off Operation for Hefei Light Source	2719
	W. Xu, D. Jia, S.P. Jiang, C. Li, J.Y. Li, J.G. Wang, K. Xuan, Y.L. Yang, Q.B. Zeng, X. Zhou USTC/NSRL, Hefei, Anhui, People's Republic of China
	Hefei Light Source has successfully finished a major upgrade project and has been officially opened to users since January 2015. The upgrade project mainly includes increasing the linac injector energy from 200 MeV to 800 MeV which is the same as the ring energy, changing the ring lattice structure from TBA to DBA in order to provide more straight sections for insertion devices while keeping the circumference unchanged, and lowering the beam emittance to obtain higher photon brightness. Before the upgrade project, decay mode is the only choice for the operation of Hefei Light Source. This is because the injected beam from the linac injector needs to be ramped up to 800 MeV after injection. At prensent we have the conditions to operate Hefei Light Source with top-off mode since the linac can perform full-energy and bunch-by-bunch injection. The main challenge for the top-off operation is to control the radiation dose for personal and equipment safety, and to maintain high stability and reliability of the injector. In this paper, we report our work on the top-off operation project for Hefei Light Source.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-WEPAB064
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THPIK064	Beam Lifetime Analysis of HLS-II Storage Ring	4242
	K. Xuan, C. Li, J.Y. Li, G. Liu, G. Liu, J.G. Wang, L. Wang, W. Xu USTC/NSRL, Hefei, Anhui, People's Republic of China
	Beam lifetime is one of the important parameters of electron storage rings, which can describe the particle loss rate quantitatively and is restrict by quantum lifetime, beam-gas scattering and Touschek effect. The upgrade project of Hefei light source, named HLSII, has greatly improved the performance of the light source. The beam lifetime has been maintained at more than 5 hours. In this paper, a combined analysis method is derived by the analysis of the beam lifetime, and the method is applied to the HLSII storage ring. The experimental results show that this method is simple and reliable for the analysis of the Touschek lifetime and beam-gas scattering lifetime.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-THPIK064
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Paper

Title

Page

Introduction of Beam Position Monitor System in the HLS II Storage Ring

319

F.F. Wu, L. Lin, X.Y. Liu, P. Lu, B.G. Sun, L.L. Tang, J.G. Wang, J.H. Wei, K. Xuan, Y.L. Yang, T.Y. Zhou, Z.R. Zhou
USTC/NSRL, Hefei, Anhui, People's Republic of China

Funding: Supported by the National Key Research and Development Program of China (No. 2016YFA0402000) Supported by the National Science Foundation of China (11575181, 11605202)
Beam position monitor(BPM) system for the HLS II storage ring were designed in the HLS II upgrade project. This system is composed of BPM, BPM processor embedded with IOC and OPI. Every component of BPM system is introduced in this paper. BPM processors have different modes of data, such as ADC data, turn-by-turn(TBT) data, fast acquirement(FA) data and slow acquirement(SA) data. Different modes of data are used to different applications. Two applications based on SA data of the BPM system, such as BBA for quadrupole magnet center measurement and beam closed orbit feedback, are described in detail. The result of BBA shows that most magnetic centers of quadrupole magnets are in the range of [-1 mm, 1 mm] with respect to BPM electric centers. The result of beam closed orbit feedback shows that beam orbit stability when the closed orbit feedback system is on is far better than that when the closed orbit feedback system is off.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-MOPAB085

Export •

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

MOPIK085

Linear Optics Calibration at the HLS-II Storage Ring Using Model Independent Analysis

727

G. Liu, L. Wang, F.F. Wu, K. Xuan
USTC/NSRL, Hefei, Anhui, People's Republic of China

Linear optics are the main lattice parameters characterizing the linear properties of storage rings. Especially for beta function and phase advance, they are the basic lattice functions which must be accurately calibrated to ensure high quality operation of the machine. Model Independent Analysis (MIA), which adopts mathematical statistical methods to extract the effective lattice information of storage rings by directly analyzing the turn-by-turn beam-position-monitor (BPM) measurements, has been applied at HLS-II to calibrate the linear optics model of the storage ring. The measurements of the turn-by-turn BPM data with all of the 32 BPMs are reported in this paper. The calibration results of the beta function using MIA are presented.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-MOPIK085

Export •

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

MOPIK087

Development of a Tune Knob for the HLS-II Storage Ring

730

S.W. Wang, J.Y. Li, W.B. Wu, W. Xu, K. Xuan, X. Zhou
USTC/NSRL, Hefei, Anhui, People's Republic of China

A tune knob is a useful tool for lattice setup and machine studies in a storage ring. It is used to adjust the transverse tunes with a small impact on the beam dynamics. A global tune knob is designed for the Hefei Light Source (HLS). In the tune knob, the quadrupoles are grouped into four families and are symmetrically adjusted. Methodical Accelerator Design-X (MAD-X) is used to calculate the coefficients of the tune knob and the Accelerator Toolbox (AT) is used to double check the accuracy of the tune knob. The chromaticity is corrected by the sextupoles in the storage ring. This paper reports preliminary simulation results of the tune knob for HLS. The beta function deviations are also studied.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-MOPIK087

Export •

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

TUPIK063

The Configurable Software Interlock System for HLS-II

1836

SUSPSIK086

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

Y. Song, G. Liu, K. Xuan
USTC/NSRL, Hefei, Anhui, People's Republic of China

The interlock system is an essential component for an accelerator facility. A configurable software interlock system(SIS) is designed for Hefei Light Source II (HLS-II), which complements the hardware interlock system to ensure equipment and operators' safety. The system is developed using Python under the EPICS framework with the method of separating the configuration file from the interlock program. The interlock logic is completely determined by the configuration file and its nested tree structure is easy to expand. The test results indicate that the new software interlock system is reliable, flexible and convenient to operate. This paper will describe the design and the construction of HLS-II SIS.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-TUPIK063

Export •

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

TUPIK066

Beam Loss Simulation and Radiation Shielding for Top-Off Operation of Hefei Light Source

1845

X. Zhou, J.Y. Li, J.G. Wang, S.W. Wang, W.B. Wu, W. Xu, K. Xuan, Q.B. Zeng
USTC/NSRL, Hefei, Anhui, People's Republic of China

The Hefei Light Source (HLS) is undergoing a series of upgrades to prepare for the top-off operation. To ensure radiation safety in the experimental hall under abnormal beam loss, simulations under various system errors in the HLS storage ring are performed to get in-depth understanding of the induced radiation nature. To make the radiation shielding more effective, a beam scraper is used to decrease the aperture opening of the vacuum chamber, and additional shielding is installed around the scraper. Simulation and beam test results are reported in this paper.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-TUPIK066

Export •

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

WEPAB063

Considerations on Developing a Dedicated Terahertz Light Source Based on the HLS-II Storage Ring

2716

S.W. Wang, J.Y. Li, W.B. Wu, W. Xu, K. Xuan, X. Zhou
USTC/NSRL, Hefei, Anhui, People's Republic of China

There is an increasing interest in generating terahertz radiation for different kinds of researches. A high-power terahertz light source can be realized through coherent synchrotron radiation from a storage ring. The radiation power of coherent synchrotron radiation is proportional to square of the number of electrons in a bunch. To generate coherent synchrotron radiation, the electron bunch length should be shorter than its radiation wavelength. This paper presents our preliminary study on developing a terahertz light source based on Hefei Light Source. We will introduce the status of Hefei Light Source (HLS) and discusses the approach to change it to a dedicated Terahertz light source using coherent synchrotron radiation. Several schemes are proposed to shorten the electron bunch length in the storage ring, including using a low alpha lattice, adopting a magnetic chicane and upgrading the RF system with much higher frequency. The related beam instabilities are also analyzed to predict the beam current threshold.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-WEPAB063

Export •

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

WEPAB064

Upgrade Project on Top-Off Operation for Hefei Light Source

2719

W. Xu, D. Jia, S.P. Jiang, C. Li, J.Y. Li, J.G. Wang, K. Xuan, Y.L. Yang, Q.B. Zeng, X. Zhou
USTC/NSRL, Hefei, Anhui, People's Republic of China

Hefei Light Source has successfully finished a major upgrade project and has been officially opened to users since January 2015. The upgrade project mainly includes increasing the linac injector energy from 200 MeV to 800 MeV which is the same as the ring energy, changing the ring lattice structure from TBA to DBA in order to provide more straight sections for insertion devices while keeping the circumference unchanged, and lowering the beam emittance to obtain higher photon brightness. Before the upgrade project, decay mode is the only choice for the operation of Hefei Light Source. This is because the injected beam from the linac injector needs to be ramped up to 800 MeV after injection. At prensent we have the conditions to operate Hefei Light Source with top-off mode since the linac can perform full-energy and bunch-by-bunch injection. The main challenge for the top-off operation is to control the radiation dose for personal and equipment safety, and to maintain high stability and reliability of the injector. In this paper, we report our work on the top-off operation project for Hefei Light Source.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-WEPAB064

Export •

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

THPIK064

Beam Lifetime Analysis of HLS-II Storage Ring

4242

K. Xuan, C. Li, J.Y. Li, G. Liu, G. Liu, J.G. Wang, L. Wang, W. Xu
USTC/NSRL, Hefei, Anhui, People's Republic of China

Beam lifetime is one of the important parameters of electron storage rings, which can describe the particle loss rate quantitatively and is restrict by quantum lifetime, beam-gas scattering and Touschek effect. The upgrade project of Hefei light source, named HLSII, has greatly improved the performance of the light source. The beam lifetime has been maintained at more than 5 hours. In this paper, a combined analysis method is derived by the analysis of the beam lifetime, and the method is applied to the HLSII storage ring. The experimental results show that this method is simple and reliable for the analysis of the Touschek lifetime and beam-gas scattering lifetime.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-THPIK064

Export •

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