Isomer yield ratios of 133Te, 134I, 135Xe in photofission of 235U with 17 MeV bremsstrahlung

Abstract

The isomeric yield ratios of 133Te, 134I, 135Xe in the photofission of 235U with bremsstrahlung with the end-point energy 17 MeV are measured. The contributions to the isomeric yield ratios produced by β-decay from nuclei of parent isobaric chain are taken into account. The distribution and average value of angular mo-mentum of the primary fission fragments are determined by the statistical model analysis. The codes EMPIRE 3.2 and TALYS 1.4 are applied for calculations of gamma-transitions to the isomeric and ground states. Dependence of determined distributions and average values of angular momentum on shapes of the radiative strength func-tions and the nuclear level densities are studied.

Keywords

• isomeric yield ratios
• photofission
• statistical model analysis
• average angular momentum