Measurement of isomeric yield ratios for Zr-90(gamma, n)Zr-89m,Zr-g, Zr-nat(gamma, xn1P)Y-86m,Y-g, and Y-89(gamma, xn)Y-87m,Y-g,Y-86m,Y-g reactions with 50-, 60-, and 70-MeV bremsstrahlung

Abstract

We measured the isomeric yield ratios in the photonuclear reactions of Zr-nat(gamma, n)Zr-89m,Zr-g, Zr-nat(gamma, xn1p)Y-86m,Y-g, and 89Y(gamma, xn)Y-87m,Y-g,Y-86m,Y-g by the activation method. The high-purity natural Zr and Y metallic foils in disc shape were irradiated with uncollimated bremsstrahlung beams of 50-, 60-, and 70-MeV generated from an electron linear accelerator at Pohang Accelerator Laboratory. The induced activities in the irradiated foils were measured by the high-resolution gamma-ray spectrometric system consisting of a high-purity germanium detector and a multichannel analyzer. The obtained isomeric yield ratios in the formation of Zr-89m,Zr-g, Y-87m,Y-g, and Y-86m,Y-g are compared with the corresponding values found in the literature. The measured isomeric yield ratios at the bremsstrahlung energies of 50-, 60-, and 70-MeV are the first measurement except Y-87 at 50-MeV bremsstrahlung. (C) 2009 Elsevier B.V. All rights reserved.