Author: Gao, J.
Paper Title Page
TUPPC023 Waist Corrections at the Interaction Point of ATF2 in the Presence of IPBSM Fringe Rotations and Input Beam Sigma13, Sigma24 1212
 
  • S. Bai, J. Gao
    IHEP, Beijing, People's Republic of China
  • P. Bambade
    LAL, Orsay, France
 
  The ATF2 project is the final focus system prototype for ILC and CLIC linear collider projects, with a purpose to reach a 37nm vertical beam size at the interaction point. In beam tuning towards the goal beam size, the presence of a tilt of the IP Shintake monitor fringe pattern with respect to the x-y coordinate system of the beam (or equivalently a σ13 correlation), as well as a σ24 correlation, can break the orthogonality in the main σ34 and σ32 waist corrections during the minimization and result in larger vertical beam sizes at IP. Both effects are studied, analytically and in simulation, and a practical procedure is suggested for diagnosing the presence of a residual fringe tilt, by measuring the influence of the horizontal waist correction on the minimum vertical beam size.  
 
WEPPR057 On the Single Bunch Longitudinal Collective Effects in BEPCII 3054
 
  • D. Wang, Z. Duan, J. Gao, Y. Li, L. Wang, L. Wang, N. Wang
    IHEP, Beijing, People's Republic of China
 
  Funding: National Natural Science Foundation of China,project 11175192.
In order to study the single bunch longitudinal instability in BEPCII, experiments on the bunch lengthening phenomenon were made. By analyzing the experimental data based on the Gao’s theory, the longitudinal loss factor for the bunch are obtained. Also, the total wake potential and the inductance of the machine are estimated.
 
 
WEPPR066 Effects of the External Wakefield from the CLIC PETS 3078
 
  • A. Latina, D. Schulte
    CERN, Geneva, Switzerland
  • J. Gao, Y. Wang
    IHEP, Beijing, People's Republic of China
 
  The CLIC main linac accelerating structures will be powered by the Power Extraction and Transfer Structure (PETS) located in the drive beam decelerators. Misalignments of the PETS will excite dipolar modes in the couplers of the main linac structures that will kick the beam leading to beam quality degradation. In this paper, the impact of such dipolar kicks is studied, and tolerances, based on analytical estimations, are found both in the single- and the multi-bunch regimes. Numerical simulation obtained using the tracking code PLACET are shown to confirm the analytical estimates.