Development of the neutron resonance densitometry using a pulsed neutron source, 5; Influence of neutron pulse width and flight distance on the performance of the neutron resonance densitometry

Takamine, Jun ; Harada, Hideo   ; Kureta, Masatoshi   ; Koizumi, Mitsuo ; Kitatani, Fumito  ; Tsuchiya, Harufumi ; Iimura, Hideki  ; Kimura, Atsushi   

Neutron resonance densitometry (NRD) has been proposed to quantify nuclearmaterials in melted fuel that will be removed from the Fukushima Daiichi Nuclear Power Plant. NRD is based on a combination of neutron resonancetransmission analysis (NRTA) and neutron resonance capture analysis. The major performance of NRTA system using a pulsed neutron source, such as S/N ratio and energy resolution, is determined by the flight distance and pulse width of the neutron source mainly. In this study, using a Monte Carlo simulation code, the NRTA of uranium and plutonium isotopes was simulated. the influence of quantitative accuracy of uranium and plutonium isotopes was evaluated with changing the flight distance and the pulse width.