High intensity chopper spectrometer 4SEASONS at J-PARC

Kajimoto, Ryoichi  ; Yokoo, Tetsuya*; Nakajima, Kenji  ; Nakamura, Mitsutaka   ; Soyama, Kazuhiko  ; Ino, Takashi*; Shamoto, Shinichi  ; Fujita, Masaki*; Oyama, Kenji*; Hiraka, Haruhiro*; Yamada, Kazuyoshi*; Arai, Masatoshi

We are developing a new chopper-type neutron inelastic spectrometer 4SEASONS for the spallation neutron source at J-PARC. This spectrometer has middle energy resolution and two orders higher efficiency than the ones at ISIS for a single crystal measurement. With this spectrometer, we try to explore novel quantum phenomena, in particular, the mechanism of the high- superconductivity. The high flux at a sample is achieved by incorporating the well designed transport devices in addition to the high flux of the source. The energy resolution is estimated to be 5-6% at = 0. Furthermore, the most distinguishing feature of 4SEASONS is the availability of the repetition rate multiplication (RRM) method. The RRM method enables us to utilize many 's at the same time, which will increase the efficiency of the measurement more than five times and make the survey of 4D space of - much easier.