Independent isomer yields of Sb and Te isotopes in thermal-neutron fission of 233U, 235U and 239Pu

Abstract Independent isomer yields of 130 Sb(5 + , 8 − ), 132 Sb(4 + , 8 − ), 131 Te( 3 2 + , 11 2 − ) and 133 Te ( 3 2 + , 11 2 − ) in the thermal-neutron fission of 233 U ( 5 2 + ), 235 U ( 7 2 − ) and 239 Pu ( 1 2 + ), and those of 128 Sb(5 + , 8 − ) for 233 U and 239 Pu were measured by the conventional radiochemical method. The mean angular momentum − J z.xl;h of the primary fragments has been deduced from the isomer-yield ratios. The result may indicate that the value of − J tends to decrease as the number of neutrons in the Sb and Te isotopes approaches the neutron magic number, and is independent of the angular momentum of the fissioning nucleus.