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Title: Beam Energy Drift and Energy Feedback System in the PLS 2.5GeV Linac

Abstract

In PAL{sub X}FEL, the specifications of the beam energy spread and rf phase are 0.03 %(rms) and 0.01 degrees(rms) respectively. We examined the rf performance in the present PLS 2.5 GeV Linac. The beam energy is changed as much as 0.8% by cooling temperature, air condition, and modulator high voltage jitter. The main factor to change the beam energy is the rf phase drift according to the variation of environmental condition. Dependence of the beam position drift on the rf phase was also examined. For the improvement of the injection beam stability, rf phase feedback system is designed and tested. This paper describes the rf phase feedback and the beam energy feedback system.

Authors:
; ; ; ; ; ; ;  [1]
  1. Pohang Accelerator Laboratory, POSTECH, San31, Hyoja-dong, Nam-gu, Pohang, 790-784 (Korea, Republic of)
Publication Date:
OSTI Identifier:
21043422
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 879; Journal Issue: 1; Conference: 9. international conference on synchrotron radiation instrumentation, Daegu (Korea, Republic of), 28 May - 2 Jun 2006; Other Information: DOI: 10.1063/1.2436047; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
43 PARTICLE ACCELERATORS; BEAM INJECTION; BEAM POSITION; CONTROL SYSTEMS; COOLING; ELECTRIC POTENTIAL; FEEDBACK; FREE ELECTRON LASERS; GEV RANGE; LASER RADIATION; LINEAR ACCELERATORS; PERFORMANCE; POHANG LIGHT SOURCE

Citation Formats

Hwang, W. H., Kim, H. G., Lee, W. W., Kim, S. C., Han, Y. J., Huang, J. Y., Choi, J. H., and Ko, I. S. Beam Energy Drift and Energy Feedback System in the PLS 2.5GeV Linac. United States: N. p., 2007. Web. doi:10.1063/1.2436047.
Hwang, W. H., Kim, H. G., Lee, W. W., Kim, S. C., Han, Y. J., Huang, J. Y., Choi, J. H., & Ko, I. S. Beam Energy Drift and Energy Feedback System in the PLS 2.5GeV Linac. United States. doi:10.1063/1.2436047.
Hwang, W. H., Kim, H. G., Lee, W. W., Kim, S. C., Han, Y. J., Huang, J. Y., Choi, J. H., and Ko, I. S. Fri . "Beam Energy Drift and Energy Feedback System in the PLS 2.5GeV Linac". United States. doi:10.1063/1.2436047.
@article{osti_21043422,
title = {Beam Energy Drift and Energy Feedback System in the PLS 2.5GeV Linac},
author = {Hwang, W. H. and Kim, H. G. and Lee, W. W. and Kim, S. C. and Han, Y. J. and Huang, J. Y. and Choi, J. H. and Ko, I. S.},
abstractNote = {In PAL{sub X}FEL, the specifications of the beam energy spread and rf phase are 0.03 %(rms) and 0.01 degrees(rms) respectively. We examined the rf performance in the present PLS 2.5 GeV Linac. The beam energy is changed as much as 0.8% by cooling temperature, air condition, and modulator high voltage jitter. The main factor to change the beam energy is the rf phase drift according to the variation of environmental condition. Dependence of the beam position drift on the rf phase was also examined. For the improvement of the injection beam stability, rf phase feedback system is designed and tested. This paper describes the rf phase feedback and the beam energy feedback system.},
doi = {10.1063/1.2436047},
journal = {AIP Conference Proceedings},
number = 1,
volume = 879,
place = {United States},
year = {Fri Jan 19 00:00:00 EST 2007},
month = {Fri Jan 19 00:00:00 EST 2007}
}
  • The change in relative phase between the accelerating rf fields and the beam bunches is the dominant factor of beam-energy change in linear accelerators. Major factors of the changing rf phase are modulator high voltage jitters in the short term and drifts in environmental conditions in the long term. We have investigated influences of cooling water and air temperature changes on the rf phase and beam energy drifts in the PLS 2.5-GeV linear accelerator. In this article, we describe how the environmental factors change the beam energy drifts.
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