2012 年 9 巻 1 号 p. 30-40
The J-PARC main ring synchrotron (MR) has started users operation since 2009. The MR has two beam extraction systems. One is a fast extraction system for beam delivery to the neutrino beam line of the Tokai-to-Kamioka (T2K) experiment. Other is a slow extraction system for beam delivery to the hadron experimental hall. After nine-month beam shutdown caused by the Great East Japan Earthquake, the J-PARC facility resumed beam operation since December 2012. The MR delivers the 150 kW beam to the T2K experiment and 3-5 kW beam to users in the hadron experimental hall. In this paper, status of the MR high power beam operation is presented. Some improvements planned in near future for the beam intensity upgrade are also discussed.