Cross-section measurements for short-lived isotopes of 46Ti, 75As and 92Mo at the neutron energies from 13.6 to 14.9 MeV

Cross-sections were measured at neutron energies from 13.6 to 14.9 MeV for the reactions ⁴⁶Ti(n,p) ^46mSc, ⁷⁵As(n,p) ^75mGe and ⁹²Mo(n,2n) ^91mMo leading to short-lived products. Corrections were made for the effects of gamma ray attenuation, coincidence summing, pulse pile-up, dead time, neutron flux fluctuations and scattered low energy neutrons. Statistical model calculations taking into account precompound effects were also performed.     

雨水中短寿命放射性核素研究及应用

采用一般的放射性测量仪器,通过测定雨水中的γ射线,对雨水中的短帮助放射性核素进行了研究。实验表明,几乎所有的降雨都存在短寿命放射性核素。能谱分析结果表明：这些短寿命放射性核素主要为^218Po、^214Pb和^214Bi。对雨水天然放射性的产生机理进行了分析和探讨,认为水汽凝结、下降雨滴的碰并和对空气的冲刷是雨水放射性产生的原因。探讨了雨水的放射性对地面γ测量、^210Po法测量等放射笥找矿方法的影响。