Correlation study of a beam-position monitor and a photon-beam-position monitor in the PLS-II

• Published in: Journal of the Korean Physical Society Vol. 66; no. 2; pp. 167 - 170
• Main Authors: Kim, Changbum, Shin, Seunghwan, Hwang, Ilmoon, Lee, Byung-Joon, Joo, Young-Do, Ha, Taekyun, Yoon, Jong Chel, Kim, Ghyung Hwa, Kim, Mungyung, Lee, Eun Hee, Kim, Ilyou, Huang, Jung-Yun
• Format: Journal Article
• Language: English
• Published: Seoul The Korean Physical Society 01.01.2015; 한국물리학회
• Subjects: Mathematical and Computational Physics; Particle and Nuclear Physics; Physics; Physics and Astronomy; Theoretical; 물리학; Orbit feedback system; Photon-beam-position monitor; Beam-position monitor; PLS-II
• ISSN: 0374-4884; 1976-8524
• DOI: 10.3938/jkps.66.167

The beam stability is one of the most important issues for the user service of the synchrotron radiation facility. After the upgrade of the Pohang Light Source (PLS-II), the electron-beam orbit is maintained within a root-mean-squred (rms) 1- μ m range by using an orbit feedback system. However, that does not guarantee the radiation stability at the end of the beamline because unknown factors, such as focusing mirrors and double-crystal monocrometers, are present in the beamline. As a first step to solve this problem, photon-beam-position monitors (PBPMs) are installed in the front ends of the beamline to monitor the radiation stability. If the radiation is stable at the starting point of the beamline, we can move to the other components downstream that make the radiation unstable. In this paper, a correlation study will be presented between the beam-position monitor (BPM) and the PBPM. In addition, the effect of the orbit feedback system on the correlation will be described.