title: Fast response neutron emission monitor for fusion reactor using stilbene scintillator and Flash-ADC.
abstract: The stilbene neutron detector which has been used for neutron emission profile monitoring in JT-60U has been improved, to respond to the requirement to observe the high-frequency phenomena in megahertz region such as toroidicity-induced Alfvén Eigen mode in burning plasma as well as the spatial profile and the energy spectrum. This high-frequency phenomenon is of great interest and one of the key issues in plasma physics in recent years. To achieve a fast response in the stilbene detector, a Flash-ADC is applied and the wave form of the anode signal stored directly, and neutron/gamma discrimination was carried out via software with a new scheme for data acquisition mode to extend the count rate limit to MHz region from 1.3 x 10(5) neutron/s in the past, and confirmed the adequacy of the method.
authors.affiliation: Cyclotron and Radioisotope Center, Tohoku University, Aoba 6-3, Aramaki, Aoba-ku, Sendai, Miyagi 980-8578, Japan. itogat@cyric.tohoku.ac.jp
authors.forename: T
authors.initials: T
authors.lastname: Itoga
authors.forename: M
authors.initials: M
authors.lastname: Ishikawa
authors.forename: M
authors.initials: M
authors.lastname: Baba
authors.forename: T
authors.initials: T
authors.lastname: Okuji
authors.forename: T
authors.initials: T
authors.lastname: Oishi
authors.forename: M
authors.initials: M
authors.lastname: Nakhostin
authors.forename: T
authors.initials: T
authors.lastname: Nishitani
mesh_terms: D000703:Analog-Digital Conversion; D004867:Equipment Design; D019544:Equipment Failure Analysis; D009502:Neutrons; D009681:Nuclear Fusion; D009688:Nuclear Reactors / Q000295:instrumentation*; D016273:Occupational Exposure / Q000032:analysis*; D011829:Radiation Dosage; D011834:Radiation Monitoring / Q000295:instrumentation* / Q000379:methods; D011835:Radiation Protection / Q000295:instrumentation* / Q000379:methods; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013267:Stilbenes / Q000528:radiation effects*
chemical_list: D013267:Stilbenes