Fission Barriers of Compound Superheavy Nuclei

TL;DR

This study uses nuclear density functional theory to analyze how fission barriers of superheavy nuclei depend on excitation energy, revealing differences between cold and hot fusion-produced nuclei and their impact on nuclear stability.

Contribution

It introduces a self-consistent approach to evaluate isentropic fission barriers and compares them with isothermal models for superheavy nuclei.

Findings

Fission barriers decrease more rapidly with excitation energy in cold fusion nuclei.

The difference between ground-state and saddle-point temperatures explains barrier behavior.

Particle gas effects are negligible within studied temperature ranges.

Abstract

The dependence of fission barriers on the excitation energy of the compound nucleus impacts the survival probability of superheavy nuclei synthesized in heavy-ion fusion reactions. In this work, we investigate the isentropic fission barriers by means of the self-consistent nuclear density functional theory. The relationship between isothermal and isentropic descriptions is demonstrated. Calculations have been carried out for $^{264}$Fm, $^{272}$Ds, $^{278}$112, $^{292}$114, and $^{312}$124. For nuclei around $^{278}$112 produced in "cold fusion" reactions, we predict a more rapid decrease of fission barriers with excitation energy as compared to the nuclei around $^{292}$114 synthesized in "hot fusion" experiments. This is explained in terms of the difference between the ground-state and saddle-point temperatures. The effect of the particle gas is found to be negligible in the range of temperatures studied.