Isomeric yields of¹³⁰Sb,¹³²Sb,¹³⁴I, and¹³⁶I in the thermal neutron fission of²³⁵U

Abstract

Isomer yield ratios of¹³⁰Sb,¹³²Sb,¹³⁴I and¹³⁶I isomers formed in the thermal neutron fission of²³⁵U have been calculated from our previous experimental studies that led to the identification of these species. In those studies the iodine and antimony fractions formed in fission were rapidly separated and the decay of γ-rays belonging to each isomer pair were followed using Ge(Li) detectors and a multichannel analyzer. The isomer ratios were calculated from growth and decay considerations of these γ-rays. The results are compared with the recently published values obtained with an on-line isotope separator, those from LOHENGRIN, and those from model calculations. Angular momenta of fission fragments corresponding to the measured isomer yields have also been calculated.