• M. Tobiyama, Y.H. Chin, Y. Kurimoto, T. Obina, M. Tejima, T. Toyama
  KEK, Ibaraki
• Y. Shobuda
  JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken

Transverse bunch by bunch feedback systems for J-PARC MR accelerator has been designed and tested. Bunch positions are detected by Log-ratio position detection systems with center frequency of 12 MHz. The digital filter which consists of two LLRF4 boards samples the position signal with 64 times of RF frequency. Up to four sets of 16 tap FIR filter with one-turn delay and digital shift gain can be used. Preliminary results of beam test of the system are also shown.