快中子诱发^(238)U裂变中子能谱的核-4乳胶测量

Study on N-4 Nuclear Emulsion Measuring Fission Neutron Spectrum of ^(238)U Induced by 2.5 MeV Neutron

介绍了用核-4乳胶测量2.5 MeV中子诱发^(238) U裂变瞬发中子谱的实验条件和布局以及核乳胶中反冲质子径迹的显微镜读取和处理,并采用蒙特卡罗程序SRIM和拟合方法导出了该类乳胶中反冲质子的能量-射程解析关系式,进而反推得到了核乳胶处的裂变中子相对能谱,并进行了修正,最后将实验结果与经典的Maxwell理论模型计算谱进行了比较。结果表明,二者在不确定度范围内符合较好,验证了核-4乳胶在测量裂变中子谱高能段的有效性。

The prompt fission neutron spectrum of 238U sample was measured by home-made N-4 nuclear emulsion. Details like the experimental layout and conditions, the track data reading, processing and correction were described. Also the relation of energy-range for recoil protons in the N-4 nuclear emulsion was derived by Monte Carlo simulation and fitting method. The fission neutron spectrum of N-4 nuclear emulsion was obtained, and the spectrum was corrected. The experimental results were compared with those of Maxwell model. The results show that they are in good agreement within the range of uncertainty, and the availability of N-4 nuclear emulsion in the measurement of high-energy segment of the prompt fission neutron spectrum is proved.