Simulations of magnetic field effects on 3-GeV proton beam brought by magnets for muon beam in future proton beam transport line of J-PARC

Yamaguchi, Yuji; Kondo, Yasuhiro; Meigo, Shinichiro; Shinozaki, Shinichi; Takayanagi, Tomohiro; Fujimori, Hiroshi*; Kawamura, Naritoshi*

Journal of Physics; Conference Series, 3094(1), p.012023_1 - 012023_5, 2025/09

https://doi.org/10.1088/1742-6596/3094/1/012023

The 3-GeV proton beam from the rapid cycling synchrotron (RCS) of J-PARC is transported to the spallation neutron source at Materials and Life Science Experimental Facility (MLF) by a 3-GeV RCS to Neutron facility Beam Transport (3NBT) line. Recently, the first design idea of a new proton beam transport line has been proposed for a future target station of the MLF (TS2). In the present study, proton beam transport is simulated near the TS2 target where a bending magnet and a solenoid are located for muon beam transport. The purposes are to clarify the magnetic field effects on the proton beam by the magnets and to present a method to correct each effect. Orbit deviation by the bending magnet and vertical size expansion due to profile rotation by the solenoid can be corrected by installing additional bending magnets and a solenoid with reversal magnetic field, respectively. The correction method is expected to be effective and also needs to be studied further for detail design.