Measurement of radiation skyshine with D–T neutron source

Autor: Isao Murata, Jun-ichi Hori, Teruko Sawamura, Takeo Nishitani, Kentaro Ochiai, Shun-ichi Tanaka, R. Tanaka, Akito Takahashi, Masayuki Wada, C. Kutsukake, Masashi Wakisaka, Makoto Nakao, Junichi Kaneko, Michinori Yamauchi, Shigeo Yoshida, Satoshi Sato
Rok vydání: 2003
Předmět:
Zdroj: Fusion Engineering and Design. 69:637-641
ISSN: 0920-3796
DOI: 10.1016/s0920-3796(03)00196-0
Popis: The D–T neutron skyshine experiments have been carried out at the Fusion Neutronics Source (FNS) of JAERI with the neutron yield of ∼1.7×1011 n/s. The concrete thickness of the roof and the wall of a FNS target room are 1.15 and 2 m, respectively. The FNS skyshine port with a size of 0.9×0.9 m2 was open during the experimental period. The radiation dose rate outside the target room was measured a maximum distance of 550 m from the D–T target point with a spherical rem-counter. Secondary gamma-rays were measured with high purity Ge detectors and NaI scintillation counters. The highest neutron dose was about 9×10−22 Sv/(source neutron) at a distance of 30 m from the D–T target point and the dose rate was attenuated to 4×10−24 Sv/(source neutron) at a distance of 550 m. The measured neutron dose distribution was analyzed with Monte Carlo code MCNP-4B and a simple line source model. The MCNP calculation overestimates the neutron dose in the distance range larger than 230 m. The line source model agrees well with the experimental results within the distance of 350 m.
Databáze: OpenAIRE