Eur. Phys. J. A (2007) 33: 231-236
https://doi.org/10.1140/epja/i2007-10437-y

Regular Article - Theoretical Physics

Nuclear-charge polarization at scission in the 12 MeV proton-induced fission of ²³²Th

¹ Japan Atomic Energy Agency, 319-1195, Tokai-mura, Naka-gun, Ibaraki, Japan
² Tokyo Metropolitan University, 192-0397, Minami-Ohsawa, Hachioji, Tokyo, Japan

^* e-mail: nishinaka.ichiro@jaea.go.jp

Received: 7 May 2007
Accepted: 7 July 2007
Published online: 7 August 2007

Abstract

The most probable charges of secondary fragments, produced after neutron evaporation from primary fragments, have been evaluated using fractional cumulative and mass yields in the 12MeV proton-induced fission of ²³²Th . The nuclear-charge polarization of primary fragments at scission has been obtained by correcting the most probable charge of secondary fragments for neutron evaporation. The fragment mass dependence of the nuclear-charge polarization at scission shows good agreement with that for thermal neutron-induced fission of ²³⁵U , indicating that the nuclear-charge polarization is nearly insensitive to mass and excitation energy of the fissioning nucleus for asymmetric fission in the actinide region.