Recent progress of laser stripping POP demonstration study at J-PARC RCS

Saha, P. K.   ; Harada, Hiroyuki  ; Yoneda, Hitoki*; Michine, Yurina*; Fuchi, Aoi*; Sato, Atsushi*; Shibata, Takanori*; Kinsho, Michikazu  

We have significant progress on the preparation of POP (proof-of-principle) demonstration of 400 MeV H stripping to proton by using only lasers at J-PARC RCS. The motivation of this research is to establish H charge-exchange injection by using lasers instead of a stripper foil conventionally used at present. A short foil lifetime and residual radiation caused by the foil scattering beam loss are extremely serious issues, especially at high-intensity operation. The R&D of the laser system is in good progress through experimental studies for 3 MeV H beam at present. We developed a multi-reflection laser cavity system to reduce the seed laser power, which was also successfully tested for 3 MeV H beam neutralization in July, 2021. Further development of the whole laser system is continued to start the POP demonstration study in 2022.