IPAC2017 - List of Authors (Yang, Y.L.)

Paper	Title	Page
MOPAB080	The Development of Tune Measurement System Based on FPGA at HLSII Storage Ring	305
	Q.M. Duan, Y.L. Yang USTC/NSRL, Hefei, Anhui, People's Republic of China
	A tune measurement system based on FPGA development board is developed at HLS II. The FPGA development board based on Zynq SOC, have ADC and DAC on board. The FPGA can provide two kinds of signal for exciting the beam: parametric frequency sweep signal and bandwidth limited white noise signal. The FFT algorithms and calculation of tune are running in the ARM CPU. In order to compare performance with the original system which is based on spectrum analyzer, we did experiments with new system based FPGA and original system respectively. The experiments on HLSII storage ring show that the tune measuring accuracy have reached 0.0006 / 0.0001 in horizontal and vertical direction based on sweep frequency of FPGA-based system.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-MOPAB080
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MOPAB082	Design and Simulation of High Order Mode Cavity Bunch Length Monitor for Infrared Free Electron Laser	309
SUSPSIK076	use link to see paper's listing under its alternate paper code
	Q. Wang, X.Y. Liu, P. Lu, Q. Luo, B.G. Sun, L.L. Tang, J.H. Wei, F.F. Wu, 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 (2016YFA0401900, 2016YFA0401903); NSFC (11375178, 11575181); the Fundamental Research Funds for the Central Universities (WK2310000046) A bunch length monitor using resonant cavity has been designed for the NSRL Infrared Free Electron Laser (IR-FEL) facility. To avoid the restriction of working fre-quency caused by the beam pipe radius, the high order modes of the harmonic cavities are utilized. The position and orientation of coaxial probes are optimized to avoid interference modes which come from the cavity and beam tube according to the analysis formula of electro-magnetic field distribution. Based on the parameters of IR-FEL, a simulation is performed to verify the feasibility of the bunch length monitor. The simulation result shows that the design meets the requirements of IR-FEL, and the resolution can be better than 50 fs.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-MOPAB082
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MOPAB083	The New Beam Current Transformer for IR-FEL Facility at NSRL *	312
	J.H. Wei, H. Li, X.Y. Liu, P. Lu, B.G. Sun, J.G. Wang, Q. Wang, F.F. Wu, Y.L. Yang, T.Y. Zhou USTC/NSRL, Hefei, Anhui, People's Republic of China
	Funding: Supported by The National Science Foundation of China (Grant No. 11575181) The beam current transformer (CT) is an important part of the beam diagnostics system as a kind of non-destructive intensity measurement. The beam CT has the strong dependence of the sensitivity and time constant on the time structure of the beam. To measure the macro-pulse beam intensity with 5-10 's length and 238 MHzμpulse repetition rate in the IR-FEL, it is necessary to find a suitable material as the CT core which can meet the measure requirement of the beam current. In this paper, three different magnetic materials were tested to find out that the laminated amorphous core owned the best performance, meanwhile, the mechanical structure was designed. The finished product passed the acceptance test.
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MOPAB084	Online Measurement of Electrode Gains for Stripline Beam Position Monitor in the HLS II Storage Ring	316
	F.F. Wu, L. Lin, X.Y. Liu, P. Lu, B.G. Sun, L.L. Tang, J.G. Wang, J.H. Wei, 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) and the National Science Foundation of China (11575181, 11605202) Three axially symmetric stripline beam position monitors were installed in the HLS II storage ring and each stripline BPM was machined with button BPM together. Due to mechanical errors of stripline BPM, differences in electrode gains will lead to measurement error for beam position and mutual coupling between beam horizontal position and vertical position. So it is very important to calibrate electrode gains for axially symmetric BPM. A method was proposed to calibrate electrode gains of this kind of BPM. This method is suitable for all axially symmetric BPMs, whether stripline BPM or button BPM. The online calibrated gains were compared with offline calibrated gains and the results have shown that online and offline calibrated electrode gains were basically consistent.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-MOPAB084
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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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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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Paper

Title

Page

The Development of Tune Measurement System Based on FPGA at HLSII Storage Ring

305

Q.M. Duan, Y.L. Yang
USTC/NSRL, Hefei, Anhui, People's Republic of China

A tune measurement system based on FPGA development board is developed at HLS II. The FPGA development board based on Zynq SOC, have ADC and DAC on board. The FPGA can provide two kinds of signal for exciting the beam: parametric frequency sweep signal and bandwidth limited white noise signal. The FFT algorithms and calculation of tune are running in the ARM CPU. In order to compare performance with the original system which is based on spectrum analyzer, we did experiments with new system based FPGA and original system respectively. The experiments on HLSII storage ring show that the tune measuring accuracy have reached 0.0006 / 0.0001 in horizontal and vertical direction based on sweep frequency of FPGA-based system.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-MOPAB080

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MOPAB082

Design and Simulation of High Order Mode Cavity Bunch Length Monitor for Infrared Free Electron Laser

309

SUSPSIK076

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

Q. Wang, X.Y. Liu, P. Lu, Q. Luo, B.G. Sun, L.L. Tang, J.H. Wei, F.F. Wu, 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 (2016YFA0401900, 2016YFA0401903); NSFC (11375178, 11575181); the Fundamental Research Funds for the Central Universities (WK2310000046)
A bunch length monitor using resonant cavity has been designed for the NSRL Infrared Free Electron Laser (IR-FEL) facility. To avoid the restriction of working fre-quency caused by the beam pipe radius, the high order modes of the harmonic cavities are utilized. The position and orientation of coaxial probes are optimized to avoid interference modes which come from the cavity and beam tube according to the analysis formula of electro-magnetic field distribution. Based on the parameters of IR-FEL, a simulation is performed to verify the feasibility of the bunch length monitor. The simulation result shows that the design meets the requirements of IR-FEL, and the resolution can be better than 50 fs.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-MOPAB082

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

MOPAB083

The New Beam Current Transformer for IR-FEL Facility at NSRL *

312

J.H. Wei, H. Li, X.Y. Liu, P. Lu, B.G. Sun, J.G. Wang, Q. Wang, F.F. Wu, Y.L. Yang, T.Y. Zhou
USTC/NSRL, Hefei, Anhui, People's Republic of China

Funding: Supported by The National Science Foundation of China (Grant No. 11575181)
The beam current transformer (CT) is an important part of the beam diagnostics system as a kind of non-destructive intensity measurement. The beam CT has the strong dependence of the sensitivity and time constant on the time structure of the beam. To measure the macro-pulse beam intensity with 5-10 's length and 238 MHzμpulse repetition rate in the IR-FEL, it is necessary to find a suitable material as the CT core which can meet the measure requirement of the beam current. In this paper, three different magnetic materials were tested to find out that the laminated amorphous core owned the best performance, meanwhile, the mechanical structure was designed. The finished product passed the acceptance test.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-MOPAB083

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

MOPAB084

Online Measurement of Electrode Gains for Stripline Beam Position Monitor in the HLS II Storage Ring

316

F.F. Wu, L. Lin, X.Y. Liu, P. Lu, B.G. Sun, L.L. Tang, J.G. Wang, J.H. Wei, 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) and the National Science Foundation of China (11575181, 11605202)
Three axially symmetric stripline beam position monitors were installed in the HLS II storage ring and each stripline BPM was machined with button BPM together. Due to mechanical errors of stripline BPM, differences in electrode gains will lead to measurement error for beam position and mutual coupling between beam horizontal position and vertical position. So it is very important to calibrate electrode gains for axially symmetric BPM. A method was proposed to calibrate electrode gains of this kind of BPM. This method is suitable for all axially symmetric BPMs, whether stripline BPM or button BPM. The online calibrated gains were compared with offline calibrated gains and the results have shown that online and offline calibrated electrode gains were basically consistent.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-MOPAB084

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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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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)