Detection of H particles in MEBT2 chicane of J-PARC linac

Tamura, Jun  ; Miura, Akihiko ; Morishita, Takatoshi  ; Okabe, Kota  ; Yoshimoto, Masahiro  ; Ao, Hiroyuki*; Futatsukawa, Kenta*; Maruta, Tomofumi*; Miyao, Tomoaki*; Nemoto, Yasuo*

In the Japan Proton Accelerator Research Complex (J-PARC), H particles generated by collisions of accelerated H beams with residual gases are considered as one of the key factors of the residual radiation in the high energy accelerating section of the linac. To diagnose the H particles, the new analysis line for the H particles was installed in the matching section from the separated-type drift tube linac (SDTL) to the annular-ring coupled structure linac (ACS). In the analysis line, the accelerated H ions travel in chicane orbit by the four dipole magnets. In the beam commissioning, we directly detected the H particles by using a carbon plated installed to a wire scanner monitor and indirectly detected the H particles by using a scintillation detector. We also confirmed that the signals change with vacuum condition in the SDTL section.