Pairing strength in the relativistic mean-field theory determined from fission barrier heights of actinide nuclei and verified by pairing rotation and binding energies

TL;DR

This study determines the optimal pairing strength in the relativistic mean-field theory to accurately reproduce fission barrier heights, binding energies, and pairing rotational energies in actinide nuclei, improving theoretical predictions.

Contribution

It introduces a method to calibrate pairing strength using fission barriers and pairing rotational energies within the relativistic mean-field + BCS framework, enhancing nuclear modeling accuracy.

Findings

Increasing pairing strength by about 13% improves fission barrier reproduction.

The adjusted pairing strength better predicts binding energies of heavy nuclei.

A consistent description of fission barriers, binding energies, and pairing moments is achieved.

Abstract

We have studied strength in the BCS pairing force, used as a residual interaction to the relativistic mean-field to reproduce the height of the inner fission barriers for actinide nuclei. It was found that increasing the pairing strength by about 13% makes reproduce the inner fission barriers better over a wide range of actinide nuclei. This result was verified by using the moment-of-inertia of pairing rotational energy, which was introduced to avoid mean-field and odd-mass effects in the pairing interaction to deduce purely the pairing strength. The pairing interaction thus determined could simultaneously improve the description of the binding energy of heavy nuclei as well. As a result, a consistent picture among inner fission barrier, binding energy, and pairing moment of inertia could be obtained in terms of the relativistic mean-field + BCS theory for a broad region of the actinide nuclei.