Multipole responses in fissioning nuclei and their uncertainties

TL;DR

This paper investigates electromagnetic multipole responses in actinide nuclei using the finite amplitude method, quantifies uncertainties from functional parameterization, and explores the impact of blocking configurations across the plutonium isotopic chain.

Contribution

It extends the FAM formalism to include blocking calculations for odd-mass nuclei and analyzes response variability across isotopes with respect to nuclear deformation.

Findings

Large variability of multipole response with neutron number.

Correlation between response and nuclear ground state deformation.

Quantified systematic and statistical uncertainties in FAM calculations.

Abstract

Electromagnetic multipole responses are key inputs to model the structure, decay and reaction of atomic nuclei. With the introduction of the finite amplitude method (FAM), large-scale calculations of the nuclear linear response in heavy deformed nuclei have become possible. This work provides a detailed study of multipole responses in actinide nuclei with Skyrme energy density functionals. We quantify both systematic and statistical uncertainties induced by the functional parameterization in FAM calculations. We also extend the FAM formalism to perform blocking calculations with the equal filling approximation for odd-mass and odd-odd nuclei, and analyze the impact of blocking configurations on the response. By examining the entire plutonium isotopic chain from the proton to the neutron dripline, we find a large variability of the response with the neutron number and study how it correlates with the deformation of the nuclear ground state.