Systematic calibration of beam position monitor in the high intensity proton accelerator (J-PARC) linac

Sato, Susumu  ; Igarashi, Zenei*; Lee, S.*; Tomisawa, Tetsuo ; Hiroki, Fumio ; Kishiro, Junichi; Ikegami, Masanori*; Kondo, Yasuhiro   ; Hasegawa, Kazuo; Ueno, Akira  ; Toyama, Takeshi*; Kamikubota, Norihiko*; Nigorikawa, Kazuyuki*; Tanaka, Mikio*; Yoshikawa, Hiroshi

As a joint project of KEK and JAERI, a MW class of high intensity proton accelerator (J-PARC), consisting of Linac, 3 GeV-RCS, 50 GeV-MR, is under construction at Tokai, Japan. For this accelerator, it is required to minimize the beam loss (typically, lower than 0.11 W/m at the linac). To achieve the requirement, beam trajectory needs to be controlled with accuracy of some 100 micro-meter. The first stage of the acceleration (up to 181 MeV during the first stage of construction) is done by linac. The beam position monitor (BPM) in the linac utilizes 4 strip-line pickups (50 ohm) on the beam transportation chamber. In this paper, systematic calibration of the BPM is described.