J-PARC linac facilities and their features

The Japan Proton Accelerator Complex (J-PARC), which consists of a 600-MeV linac, a 3-GeV rapid cycling synchrotron, a 50-GeV synchrotron and experimental facilities, is not only one of the most powerful proton accelerators in the world but also a multipurpose accelerator for neutron science, muon science, nuclear and elementary particle physics, and nuclear engineering. The linac building and its conventional facilities were designed and constructed carefully in consideration of stable operation and further upgrade. The linac building, which has two stories above ground and two stories below ground, was completed in April, 2005. The conventional facilities were also completed in August 2005. The installation of the accelerator began in April 2005. The ion source, the radio-frequency quadrupole linac (RFQ), the drift tube linac (DTL) tanks, the medium energy beam transport between the RFQ and the DTL (MEBT1), and the beam transport to the 3-GeV synchrotron have already been installed. Installation of the separated-type drift tube linac (SDTL) tanks and the RF system are being continued. This paper describes the J-PARC linac facilities and their features in terms of the building and conventional facilities, as well as the present status of the linac installation.