Status and progress of the J-PARC 3 GeV RCS

J-PARC 3GeVシンクロトロンの現状と性能向上

金正 倫計  

Kinsho, Michikazu

J-PARC 3GeVシンクトロトンはMLFとMRへユーザー利用運転のために300kWのビームを安定に供給している。2台のパルス電磁石をビームラインに新たに設置し、MLFとMRからのビーム形状に対する要求に対するそれぞれの要求を満足させ、ビームロスを低減した。また、ビーム増強のための試験を実施し524kW相当のビームを2%のビームロスで、35秒間の出力に成功した。ビームロスの設計値は3%であるので、2%ビームロスは加速器の運転上十分に小さな値である。入射エネルギー181MeVでの524kW出力は、入射エネルギーが400MeVの際の1.6MWに相当するパワーであり、本ビーム試験は、設計値の1MW出力達成に向けた大きな成果である。

The J-PARC RCS has been delivered more than 300 kW beam to both the MLF and the MR with high reliability. To realize simultaneously two kinds of beam shape which are required from the MLF and the MR, two pulse dipole magnets for injection painting were installed in the beam transport line from the Linac to the RCS. It was successful to make two kinds of beam shape with injection painting bump magnets and these added pulse dipole magnets. This injection painting system is used for user operation and works well for reduction of beam losses. Not only user operation but also high power beam test was performed, and beam power of 524 kW for 35 second was achieved with low beam loss in the RCS. The loss rate was about 2% and this was acceptable because design value of the beam loss was 3%. This power corresponds to 1.6 MW for 400 MeV injection in terms of the Lasslett tune shift. In this high-intensity trial, significant progress toward design output beam power of 1 MW was demonstrated.