Author: Hung, S.B.
Paper Title Page
THPC066 A Study of Emittance Growth in a Photoinjector Linac by using PWT as Pre-accelerator 3044
 
  • A. Sadeghipanah, S.B. Hung, W.K. Lau, A.P. Lee
    NSRRC, Hsinchu, Taiwan
  • N.Y. Huang
    NTHU, Hsinchu, Taiwan
 
  The NSRRC high brightness photoinjector for light source R&D is a 2998 MHz split configuration. Our goal is to produce 1 nC bunch charge from a photo-cathode rf gun with normalized emittance of 1 mm-mrad or less. However, limited by the available power from our klystron, previous studies showed that our linac has to be equipped with focusing solenoid to help emittance control during acceleration. In order to omit the bulky focusing solenoid from the booster linac system, we considered to use two high gradient (~26 MV/m) PWT standing-wave structures to accelerate the beam previous to the linac. Studies showed that this configuration can keep the emittance as low as 1 mm-mrad while also decreasing the energy spread to half of its initial amount. The only drawback is the growth of final beam radius, which can be compensated by using a setting of quadrupole magnets.