【摘要】 252 Cf随机脉冲源方法由早期的重复脉冲源方法演变而来,是测量核系统瞬发中子衰减常数α的有效方法。采用该方法测量了钚球装配31mm、29mm厚钢反射层核系统的α,在有效信号和噪声的比例为1∶1的情况下,得到的瞬发中子衰减谱信噪比为7∶1,最小二乘拟合结果依次为2.25μs-1和3.00μs-1,拟合误差为±0.02μs-1。与Rossi-α方法的测量结果进行了比较,两种测量方法的结果差异小于1.3%。更多还原

【Abstract】 The randomly pulsed neutron method with 252Cf,which evolved from repeated pulsed-neutron method,is effective on prompt-neutron decay constant measurements.Because it’s based on time-correlated accordance,the influence of the background rays could be suppressed effectively.Using this method,subcritical measurements were performed on an alpha-phase plutonium sphere reflected by 31 mm thick and 29 mm thick steel.The proportion of useful signal and background was 1∶1 in the experiments,but in the prompt neutron decay spectrum the proportion of time-correlated signal and background was 7∶1.The prompt neutron decay constants of the measurements were 2.25 μs-1 and 3.00 μs-1 and the fitting error was ±0.02 μs-1.Comparing with the results by Rossi-α method,the difference is less than 1.3%.更多还原