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Abstract
Introduction
Phase Scan Method
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Physics

Beam Phase Measurement for Pefp Linear Accelerator *

Profile image of Han-Sung KimHan-Sung Kim

2013

Abstract

According to the commissioning plan of the PEFP proton linac, an accurate measurement of beam phase is essential, especially for setting up the RF operating parameters of DTL. Beam position monitors (BPMs) installed between DTL tanks can provide information about the beam phase as well as about the beam transverse position. By using a BPM as a beam phase monitor, beam phase can be measured without additional devices on the linac or the beam line. The signals from 4 electrodes in the BPM can be summed by using a 4-way RF combiner, by which the effect of the transverse beam offset on the phase measurement can be eliminated. The combined BPM signal (350 MHz) is mixed with LO signal (300 MHz) and down-converted to IF signal (50 MHz), then fed into the signal processing unit, where the phase information is extracted by using IQ demodulation method with a sampling frequency of 40 MHz. In this paper, the beam phase measurement system and signal processing scheme will be presented.

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References (7)

  1. Copyright c ○ 2012 by the respective authors -cc Creative Commons Attribution 3.0 (CC BY 3.0) 2A Proton Linac Projects ISBN 978-3-95450-122-9 895 Copyright c ○ 2012 by the respective authors -cc Creative Commons Attribution 3.0 (CC BY 3.0) REFERENCES
  2. K. Y. Kim, Y. S. Cho, J. Y. Kim, K. R. Kim, and B. H. Choi, "The Proton Engineering Frontier Project: Accelerator Development", J. of Korea Phys. Soc., 56 (2010) 1936.
  3. J. H. Jang, H. J. Kwon, and Y. S. Cho, "Beam Commissioning Plan of PEFP 100-MeV Linac", Proceedings of IPAC2011, (2012).
  4. H. S. Kim, Y. S. Cho, S. H. Han, J. H. Jang, Y. H. Kim, and H. J. Kwon, "Initial Test of the PEFP 20
  5. MeV DTL", Proceedings of PAC2005, (2006).
  6. J. Y. Ryu, H. J. Kwon, J. H. Jang, H. S. Kim, K. T. Seol, and Y. S. Cho, "Development of Beam Position Monitor for PEFP Linac and Beam Line", Proceedings of IPAC2011, (2012).
  7. T. L. Owens, M. B. Popovic, E. S. Mccrory, C. W. Schmidt, and L. J. Allen, "Phase Scan Signature Matching for Linac Tuning", Particle Accelerators, Vol.48, p.169, 1994.

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