Easurement of cross sections for 50Cr (n, 2n)49Cr and 52Cr (n, 2n)51Cr reactions induced by 13.5-14.6 MeV neutrons

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: Cr-50 (n, 2n)(49) Cr and Cr-52 (n, 2n)Cr-51. The cross sections of Cr-50 (n,2n)Cr-49 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 Cr-52 (n, 2n)Cr-51 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 Cr-50(n, gamma)Cr-51 reaction induced by thermal neutron to Cr-52( n, 2n)Cr-51 reaction, and the measured results are compared with published data. Neutron energies are determined by the method of cross-section ratios of Zr-90( n, 2n)Zr89m + g and Nb-93(n,2n)Nb-92m reactions, and the neutron fluencies are determined using the monitor reaction Nb-93(n,2n)Nb-92m.