THP028
ポスターセッション② 8月7日 7-1F-B 13:00-15:00
J-PARC RCSにおける1MW出力を超える利用運転に向けたビームロス低減
Beam loss mitigation for operation beyond 1 MW beam power of the J-PARC RCS
○Saha Pranab Kumar, 原田 寛之, 田村 文彦, 菖蒲田 義博, 小島 邦洸, 吉本 政弘, 沖田 英史, 岡部 晃大, 畠山 衆一郎, 仲野谷 孝充, 守屋 克洋, 地村 幹, 山田 逸平, 高柳 智弘（日本原子力研究開発機構, J-PARC）
○Pranab Kumar Saha, Hiroyuki Harada, Fumihiko Tamura, Yoshihiro Shobuda, Kunihiro Kojima, Masahiro Yoshimoto, Hidefumi Okita, Okabe Kota, Shuichiro Hatakeyama, Takamitsu Nakanoya, Katsuhiro Moriya, Motoki Chimura, Ippei Yamada, Tomohiro Takayanagi（JAEA, J-PARC）
We have performed systematic beam tests and numerical simulations for beam loss mitigation at the 3-GeV RCS of J-PARC at beyond 1 MW beam power. To ensure net 1 MW beam power to the current neutron target while beam sharing is reducing to around 85% due to the Main Ring cycle approaching faster to nearly 1 s, and construction of a 2nd neutron target, the RCS has to achieve at least 1.5 MW in the near future. Keeping the beam loss rate at the same level as the current operation at 1 MW is one of the key points to ensure a stable operation by keeping the machine activation proportional to an increase of beam power. In a recent beam study by optimizing injection beam parameters along with transverse and longitudinal paintings in the RCS, the beam loss rate at 1.5 MW is achieved to be a less than 5E-4 level. The beam loss occurs only at injection energy, well localizing at the collimator section with only 70 W loss power as compared to the collimator limit of 4 kW. The beam loss power is kept to only 1.27 times increase from that of 55 W at the current 1 MW operation to demonstrate the RCS capability to run at 1.5 MW beam power with a minimum beam loss.