Detector system of single crystal diffractometer SENJU

Kawasaki, Takuro   ; Nakamura, Tatsuya  ; Sakasai, Kaoru  ; To, Kentaro  ; Hosoya, Takaaki*; Soyama, Kazuhiko  ; Katagiri, Masaki*; Oikawa, Kenichi   ; Kaneko, Koji   ; Tamura, Itaru  ; Ohara, Takashi*   ; Kiyanagi, Ryoji  ; Nakao, Akiko*; Hanashima, Takayasu*; Munakata, Koji*

A novel time-of-flight single crystal neutron diffractometer, SENJU, is being constructed in MLF at J-PARC. The diffractometer will have 37 two-dimensional WLSF-type scintillator detectors to cover wide area of reciprocal lattice space by a single measurement. SENJU will receive first neutron in early 2012 in which 30 detectors will be installed around the sample chamber in a cylindrical arrangement and one detector will be installed just under the chamber. The maximum total covered solid angle around the sample will be 4.8 sr, which enables the efficient measurements and improves the completeness of the data. The detector for SENJU was developed based on the detector for iBIX to meet the requirement of SENJU, i.e. spatial resolution, chassis size, sensitive area and magnetic field tolerance. The 31 detectors have been already manufactured and their performances were tested by checking sources. Overview of the system and the performances of the detectors will be presented.