Current status of the injection bump system in J-PARC 3-GeV RCS

Ueno, Tomoaki; Takayanagi, Tomohiro   ; Togashi, Tomohito; Kinsho, Michikazu  

The injection bump system of the 3-GeV RCS (Rapid Cycling Synchrotron) in J-PARC (Japan Proton Accelerator Research Complex) consists of the pulse bending magnets for the injection bump orbit, which are four horizontal bending magnets (shift bump), four horizontal painting magnets (h-paint bump) and two vertical painting magnets (v-paint bump). The power supplies of the magnets are composed of multiple-connections of the IGBT (Insulated Gate Bipolar Transistor) assemblies. They excite the current waveform of the trapezoid pattern with the flat top for 500 s and the flexible decay pattern. The exciting current and magnetic field were measured. The power supplies executed the good accuracy less than 1percent deviation to programmed pattern. Furthermore, the continuous long-term with stable has been performed. In this paper, the current status of the operation of the injection bump system is described.