About ten years ago (2001) a new accelerator project to provide high-intensity proton beams proceeded into its construction phase. This project is called the J-PARC (Japan Proton Accelerator Research Complex), and it was completed about a year ago in 2009. The construction was performed under a cooperation of two institutions, KEK and JAEA. The goal of the accelerator power is 1 MW proton beams at 3 GeV, with 400 MeV Linac injector, and 0.75 MW beams at 50 GeV.
Three experimental facilities are presently available: 1) the Materials and Life Experimental Facility where pulsed neutrons and muon beams from 3 GeV are produced and utilized, 2) the Hadron Experimental Facility where kaon beams are produced, with a slow extraction mode from the 50 GeV (currently, 30 GeV is used), and 3) the Neutrino Experimental Facility with fast extraction mode from the 50 GeV ring.
I would like to overview the current status of the accelerators and experimental facilities at J-PARC, in particular, under the emphasis of what are actually going on in regard to experimental programs. I also would like to mention briefly the past history and the future scope of the J-PARC.