THPI041 　ハドロン加速器　 8月1日 国際科学イノベーション棟5階 ホワイエ 13:30-15:30

J-PARC 3-GeVシンクロトロンにおけるレーザー荷電変換入射実現のためレーザー強度を低減できる2ミラーのマルチレーザー照射システムの開発

Development of two-mirror multi-pass laser system to reduce laser power for laser stripping injection at J-PARC 3-GeV RCS

○サハ プラナブ　クマル，原田 寛之，金正 倫計（原子力機構, J-PARC），佐藤 篤（NAT），道根 百合奈，米田 仁紀（電通大, レーザー研）

○Pranab Kumar Saha, Hiroyuki Harada, Michikazu Kinsho (JAEA, J-PARC), Atsushi Sato (NAT), Yurina Michine, Hitoki Yoneda (UEC, ILS)

In the 3-GeV RCS of J-PARC, experimental studies of H- (negative hydrogen) stripping by using lasers for the charge-exchange injection (CEI) of 400 MeV H- is under preparation. The merits of H- stripping by lasers is not only to overcome the short life of the stripper foil, but also for eliminating extremely high residual radiation at injection area associated with stripper foil conventionally used for the CEI. However, requirement of high power lasers is the biggest issue to realize the laser stripping CEI. To overcome this issue, we consider simple two mirror multi-pass laser system for multiple interactions of the H- beam with reflected laser light adjusted according to the H- and photon velocities. The seed laser energy can be significantly reduced, which would be almost inversely proportional number of interactions. At present are developing such a cavity with Nd:YAG laser for H- neutralization to H0, which will be first tested for 3 MeV H- beam at J-PARC RFQ test facility. The development status of the present laser system and details of experimental strategies are presented.