IPAC2018 - List of Authors (Yu, L.Y.)

Paper	Title	Page
WEPAF027	Low Q Cavity BPM Study for the Beam Position Measurement of Nanosecond Spaced Electron Bunches	1881
	L. Yang, X. He, L.W. Zhang CAEP/IFP, Mainyang, Sichuan, People's Republic of China S.S. Cao, Y.B. Leng, L.Y. Yu, R.X. Yuan SINAP, Shanghai, People's Republic of China
	Funding: National natural science foundation of China, 11705184 Low Q cavity BPM is a key to distinguish closely spaced electron bunches allowing precise beam handling for XFEL facilities operating in a multi-bunch mode at high repetition rate up to hundreds MHz. The inter-bunch signal pollution issue becomes significant when bunch separation is down to nanosecond and causes the position detection to be increasingly overestimated. Solely relying on extreme low Q to achieve sufficient decay within bunch interval leads to appreciable interference from non-signal modes due to strong overcoupling of antenna design is required. The error imposed on measured position raises a challenge to meet the goal of high resolution. Alternatively, a concept is proposed to remove the dominant part of signal pollution at the moment of sampling by intentionally shifting the phase of the last bunch signal 90degree respect to that of current bunch signal, where signal sampling is normally taken for nanosecond spaced bunches. This quadrature phase shift is defined by properly choosing the operational frequency of dipole mode regarding to the bunch frequency. A low Q cavity BPM prototype to identify technical challenges and verify this concept is under development in the R&D plan for future XFEL with high repetition rate
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-WEPAF027
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THPML067	SXFEL Linac BPM System Development and Performance Evaluation	4794
SUSPF094	use link to see paper's listing under its alternate paper code
	F.Z. Chen, T. Wu SSRF, Shanghai, People's Republic of China J. Chen, L.W. Lai, Y.B. Leng, L.Y. Yu, R.X. Yuan SINAP, Shanghai, People's Republic of China
	Shanghai Soft X-ray Free Electron Laser (SXFEL) is a test facility to study key technologies and new FEL physics. In order to deliver high quality electron beams to the undulator section, a high resolution (better than 10 microns with 200pC beam) Linac beam position monitor system has been developed. The system consists of stripline pickup and custom designed DBPM processor. The hardware and software architecture will be introduced in this paper. The online performance evaluation results will be presented as well.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPML067
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

Low Q Cavity BPM Study for the Beam Position Measurement of Nanosecond Spaced Electron Bunches

1881

L. Yang, X. He, L.W. Zhang
CAEP/IFP, Mainyang, Sichuan, People's Republic of China
S.S. Cao, Y.B. Leng, L.Y. Yu, R.X. Yuan
SINAP, Shanghai, People's Republic of China

Funding: National natural science foundation of China, 11705184
Low Q cavity BPM is a key to distinguish closely spaced electron bunches allowing precise beam handling for XFEL facilities operating in a multi-bunch mode at high repetition rate up to hundreds MHz. The inter-bunch signal pollution issue becomes significant when bunch separation is down to nanosecond and causes the position detection to be increasingly overestimated. Solely relying on extreme low Q to achieve sufficient decay within bunch interval leads to appreciable interference from non-signal modes due to strong overcoupling of antenna design is required. The error imposed on measured position raises a challenge to meet the goal of high resolution. Alternatively, a concept is proposed to remove the dominant part of signal pollution at the moment of sampling by intentionally shifting the phase of the last bunch signal 90degree respect to that of current bunch signal, where signal sampling is normally taken for nanosecond spaced bunches. This quadrature phase shift is defined by properly choosing the operational frequency of dipole mode regarding to the bunch frequency. A low Q cavity BPM prototype to identify technical challenges and verify this concept is under development in the R&D plan for future XFEL with high repetition rate

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-WEPAF027

Export •

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

THPML067

SXFEL Linac BPM System Development and Performance Evaluation

4794

SUSPF094

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

F.Z. Chen, T. Wu
SSRF, Shanghai, People's Republic of China
J. Chen, L.W. Lai, Y.B. Leng, L.Y. Yu, R.X. Yuan
SINAP, Shanghai, People's Republic of China

Shanghai Soft X-ray Free Electron Laser (SXFEL) is a test facility to study key technologies and new FEL physics. In order to deliver high quality electron beams to the undulator section, a high resolution (better than 10 microns with 200pC beam) Linac beam position monitor system has been developed. The system consists of stripline pickup and custom designed DBPM processor. The hardware and software architecture will be introduced in this paper. The online performance evaluation results will be presented as well.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPML067

Export •

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