含氢介质内中子能谱测量

Measurement of Neutron Spectrum in Medium Containing Hydrogen

建立了直径34cm的含氢慢化球和含氢慢化球与24cm×30cm聚乙烯圆柱组合的2种基准装置,加速器的d T中子入射到含氢慢化介质,用18mm×20mm的晶体闪烁探测器测量了2种实验装置内不同位置的1MeV以上的中子能谱,并处理成不同能量阈值的中子数。在0.95置信水平下,本测量方法的不确定度为4.8%。

Two benchmarks were established. One is moderation shell containing hydrogen which is 34 cm in diameter. The other is composed of the shell and polyethylene cylinder of 24 cm×30 cm which are combinatorial. Measurement of neutron energy spectrum above 1 MeV changing with different positions of the experimental assemblies were carried out for incident neutrons from outside using d-T fusion source of accelerator. Meanwhile, the spectra were transformed integral spectrum. The scintillation detector of stilbene crystal of 18 mm×20 mm was used to measure neutron spectrum. At 0.95 level of confidence, the uncertainty of the measurement is 4.8%.