Isomeric yield ratios for the Nd-nat(gamma, xn) Nd-139m,Nd-g; 141m,Nd-g reactions in the bremsstrahlung energy region from 45 to 60 MeV

Abstract

The independent isomeric yield ratios (IR) for the Nd-139m,Nd-g and the Nd-141m,Nd-g isomeric pairs produced from the Nd-nat(gamma, xn) reactions were determined by the activation and the off-line gamma-ray spectrometric technique at the end-point bremsstrahlung energies of 45, 50, 55, and 60 MeV in the 100 MeV electron Linac of the Pohang accelerator laboratory, Korea. The present IR for the Nd-141m,Nd-g isomeric pair were compared with those from the literature measured by the bremsstrahlung and the neutron to examine the role of excitation energy. The obtained IR for the Nd-139m,Nd-g and the Nd-141m,Nd-g isomeric pairs from Nd-nat(gamma, xn) reactions were compared with those from the Pr-141(p, x), the Ce-nat(He-3, x), and the Ce-136(alpha, n) reactions to examine the role of parameters in entrance channel i.e. excitation energy and the effect of the input angular momentum. The present IR of Nd-139m,Nd-g and Nd-141m,Nd-g were compared with those calculated by using the TALYS 1.4 code as well as those from the literature data of above mentioned reactions.