Eur. Phys. J. A (2016) 52: 12
https://doi.org/10.1140/epja/i2016-16012-7

Regular Article - Theoretical Physics

Microscopic description of fission in neutron-rich radium isotopes with the Gogny energy density functional

¹ Physics Department, Kuwait University, 13060, Kuwait, Kuwait
² Departamento de Fısica Teórica, Universidad Autónoma de Madrid, 28049, Madrid, Spain

^* e-mail: luis.robledo@uam.es

Received: 6 October 2015
Accepted: 15 December 2015
Published online: 25 January 2016

Abstract

Mean-field calculations, based on the D1S, D1N and D1M parametrizations of the Gogny energy density functional, have been carried out to obtain the potential energy surfaces relevant to fission in several Ra isotopes with the neutron number . Inner and outer barrier heights as well as first and second isomer excitation energies are given. The existence of a well-developed third minimum along the fission paths of Ra nuclei is analyzed in terms of the energetics of the “fragments” defining such elongated configuration. The masses and charges of the fission fragments are studied as functions of the neutron number in the parent Ra isotope. The comparison between fission and -decay half-lives, reveals that the former becomes faster for increasing neutron numbers. Though there exists a strong variance of the results with respect to the parameters used in the computation of the spontaneous fission rate, a change in tendency is observed at with a steady increase that makes heavier neutron-rich Ra isotopes stable against fission, diminishing the importance of fission recycling in the r-process.