Characteristics of neutron multiplicity and nuclear charge polarization in proton-induced fission of U

Nishinaka, Ichiro; Tanikawa, Masashi*; Nagame, Yuichiro ; Nakahara, Hiromichi*

Characteristics of neutron multiplicity and nuclear charge polarization have been studied in the 11.5 MeV proton-induced fission of U. Fragment mass and the average neutron multiplicity were measured by a double time-of-flight method. The most probable charges of secondary fragments were evaluated from fractional cumulative and mass yields. The nuclear charge polarization of primary fragments at scission was obtained by correcting the most probable charge of secondary fragments for neutron evaporation. The results show that the nuclear charge polarization at scission is associated with the liquid drop properties of nuclei and the proton shell effect with = 50 of heavy fragments.