13.5-14.6MeV能区中子引起的50Cr(n,2n)49Cr和52Cr(n,2n)51Cr核反应截面的测量

摘要

Cross sections for (n,2n) reactions are measured on chromium isotopes at the neutron energies of 13.5-14.6MeV using the activation technique. The data of the cross sections are reported for the following reactions: 50Cr (n,2n)49Cr and 52Cr (n,2n)51Cr. The cross sections of 50Cr (n,2n)49Cr reaction are 3.4±0.2,6.8±0.3,21.5±1.0 and 25.0±1.2mb at the neutron energies of 13.5±0.3,14.1±0.2,14.4±0.3 and 14.6±0.3MeV, respectively.The cross sections of 185±10,193±9,258±13 and 332±16mb for 52Cr (n,2n)51Cr reaction are given at the neutron energies of 13.5±0.3,14.1±0.2,14.4±0.3 and 14.6±0.3MeV,respectively. The samples wrapped in cadmium foil are irradiated in order to avoid the effect of 50Cr(n,γ)51Cr reaction induced by thermal neutron to 52Cr(n,2n)51Cr reaction,and the measured results are compared with published data. Neutron energies are determined by the method of cross-section ratios of 90Zr(n,2n)89m+gZr and 93Nb(n,2n)92mNb reactions, and the neutron fluencies are determined using the monitor reaction 93Nb(n,2n)92mNb.%报告了在13.5-14.6MeV中子能区,用活化法(以93Nb(n,2n)92mNb反应截面为中子注量标准)测得的50Cr(n,2n)49Cr和52Cr(n,2n)51Cr的反应截面.由能量为13.5±0.3,14.1±0.2,14.4±0.3和14.6±0.3MeV的中子引起的50Cr(n,2n)49Cr反应截面值分别为3.4±0.2,6.8±0.3,21.5±1.0和25.0±1.2mb,52Cr(n,2n)51Cr的反应截面值分别为185±10,193±9,258±13和332±16mb.单能中子用T(d,n)4He反应获得,其能量用铌锆截面比法测定.另外,为避免热中子引发的50Cr(n,2γ)51Cr对52Cr(n,2n)51Cr反应截面的影响,在样品被辐照过程中对样品进行了包镉处理,并将实验结果与尽可能收集到的其他实验数据进行了比较.