Performance of the diode stack with resistors to suppress beam instability at the J-PARC RCS

Shobuda, Yoshihiro   ; Saha, P. K.   ; Yamada, Ippei ; Okabe, Kota  

Beam instability in the 3-GeV Rapid Cycling Synchrotron (RCS) at the Japan Proton Accelerator Research Complex (J-PARC) is primarily caused by the impedance of its eight kickers. The kicker design, with one end shorted and the other open, saves power during beam extraction but excites instability. To mitigate this, we developed a diode stack with resistors installed at the open ends of four kickers. This configuration effectively suppresses instability for smaller-emittance beams delivered to J-PARC's Main Ring (MR).