Design of the Pulse Bending Magnets for the Injection System of the 3-GeV RCS in J-PARC

The pulse bending magnets for the injection system of the 3-GeV RCS in J-PARC [1] [2] has been designed. The injection system consists of the pulsed bending magnets, which are four horizontal bending magnets (shift bump) and four horizontal painting magnets (h-paint bump) for the injection bump orbit, and two vertical painting magnets (v-paint magnet). The injection beam energy and the extraction beam power are 400 MeV and 1 MW at 25 Hz repetition rate, respectively. The acceptance to include the injection beam, the painting beam and the circulating beam at the shift bump points is a 388 mm wide and a 242 mm high. The shift bump has been designed using a 3D magnetic analysis code [3], which accomplished less than 0.4 % field deviation under 0.26 T excitation level.