Author: Cao, J.S.
Paper Title Page
MOPF20 Bunch Purity Measurement for BEPCII 252
  • H. Jun, J.S. Cao, J.H. Junhui
    IHEP, People's Republic of China
  The bunch purity is very important for time-resolved experiments. It is determined by the quality of the injection system and Touschek effect. The Beijing Electron-Positron Collider (BEPC) II was constructed for both high energy physics (HEP) and synchrotron radiation (SR) researches. It can be operated in the colliding mode and synchrotron radiation mode. It is planned to measure the beam quality in a short time of several minutes by using a timecorrelated single photon counting method. The method has a time resolution of 450 ps and a dynamic range of five orders of magnitude. In this paper, we describe our experimental set up and give a series of test results for colliding mode. We plan to set up a system which can kick out the unwanted bunches in the next stage.  
TUPC09 Longitudinal and Transverse Feedback Systems for the BEPCII Storage Rings 373
  • J. Yue, J.S. Cao, L. Ma, Y.F. Sui, L. Wang, X.Y. Zhao
    IHEP, Beijing, People's Republic of China
  In order to cure the transverse and longitudinal coupled bunch instabilities caused by higher order modes of RF cavities and resistive wall impedance in the BEPCII storage rings, two type bunch by bunch feedback system – a longitudinal feedback system and a transverse feedback system are used. The LFB system are digital system produced by Dimtel Company, the longitudinal kicker is drift-tube type borrowed from SLAC. An analog bunch-by-bunch transverse feedback system was designed and used*. The main components are two sets of beam oscillation detectors, betatron phase adjuster, notch filter and stripline kicker. This paper will describe the achieved results of curing the coupled bunch instabilities by using the LFB and TFB together with current status.
* Performance of the Transverse Coupled-Bunch Feedback System in the BEPCII Storage Ring, Proc. of 40th ICFA ABDW, 2008
poster icon Poster TUPC09 [0.356 MB]  
WEPC17 Design and Simulation of Beam Position Monitor for the CADS Injector I Proton Linac 710
  • Y.F. Sui, J.S. Cao, H.Z. Ma, Q. Ye, J. Yue
    IHEP, Beijing, People's Republic of China
  Funding: Work supported by the National Natural Science Foundation of China (NO. 11205172)
Beam Position Monitors (BPM) based on both capacitive and stripline pick-ups are designed for the China Accelerator Driven Subcritical system (C-ADS) Injector I proton LINAC. The BPM will be installed to measure the transverse beam position in the LINAC, of which the beam parameters are listed as current 10mA, energy 10MeV and the repetition frequency 325MHz. This contribution presents the status of the BPM design development and focuses on the design of the pick-ups and CST Particle Studio simulation results, including impedance, sensitivity, time domain, frequency domain response, etc. The main goal of the simulation is optimization of the mechanical design.