Repetition Rate Multiplication: RRM, an advanced measuring method planed for the backscattering instrument, at the MLF, J-PARC

Repetition Rate Multiplication: RRM; J-PARC MLFの背面反射型分光器において提案されている非弾性領域の新しい測定手法

高橋 伸明; 柴田 薫  ; 川北 至信  ; 中島 健次  ; 稲村 泰弘; 中谷 健 ; 中川 洋   ; 藤原 悟; 佐藤 卓*; 筑紫 格*; Mezei, F.*; Neumann, D. A.*; Mutka, H.*; 新井 正敏

Takahashi, Nobuaki; Shibata, Kaoru; Kawakita, Yukinobu; Nakajima, Kenji; Inamura, Yasuhiro; Nakatani, Takeshi; Nakagawa, Hiroshi; Fujiwara, Satoru; Sato, Taku*; Tsukushi, Itaru*; Mezei, F.*; Neumann, D. A.*; Mutka, H.*; Arai, Masatoshi

A TOF-BSS named has been under construction on BL02 in the MLF of J-PARC. We have estimated expected performances of several candidates under realistic neutron source parameters at MLF. The expected neutron intensity under comparable energy resolutions of the -type is 2.6 times higher than that of the BASIS-type. Consequently, we have chosen the CM with pulse-shaping device for . Pulse-shaping is a good technique from a view point of a variability of resolution. On the other hand, a neutron energy band passing through the pulse-shaping chopper is limited and thus scanning range with one phase of the chopper is narrow. Of course, also can access larger energy transfers by appropriate phasing of the pulse-shaping chopper. In addition, will be able to utilize Repetition Rate Multiplication (RRM). RRM is essentially a way to employ multiple pulse-shaped incident neutron beams to effectively increase neutron counting time to more efficiently measure the inelastic region. In this presentation we will show the chopper sequence and introduce the RRM mode of the forthcoming backscattering spectrometer in detail.