Activation cross section and isomeric cross-section ratio for the 151Eu(n,2n)150m,gEu process

Abstract The cross sections of 151 Eu(n,2n) 150m,g Eu reactions and their isomeric cross section ratios σ m /σ t have been measured experimentally. Cross sections are measured, relative to a reference 93 Nb(n,2n) 92m Nb reaction cross section, by means of the activation technique at three neutron energies 13.5, 14.1, and 14.8 MeV. Monoenergetic neutron beams were formed via the 3 H( d , n ) 4 He reaction and both Eu 2 O 3 samples and Nb monitor foils were activated together to determine the reaction cross section and the incident neutron flux. The activities induced in the reaction products were measured using high−resolution gamma ray spectroscopy. Cross sections were also evaluated theoretically using the numerical nuclear model code, TALYS-1.8 with different level density options at neutron energies varying from the reaction threshold to 20 MeV. Results are discussed and compared with the corresponding literature.