Electromagnetic Properties of the N=50 Isotones with the p35-i3 Hamiltonian

TL;DR

This paper evaluates electromagnetic properties of N=50 isotones using new Hamiltonians derived from ab-initio methods, comparing results to experimental data to understand uncertainties in nuclear shell model predictions.

Contribution

It introduces and tests new Hamiltonians based on VS-IMSRG methods, providing a detailed comparison of electromagnetic properties with experimental data.

Findings

Hamiltonians accurately reproduce magnetic and quadrupole moments.

Theoretical uncertainties are quantified through comparison of different Hamiltonians.

Results demonstrate the effectiveness of ab-initio derived interactions in shell model calculations.

Abstract

The nuclei with 50 neutrons that lie between $^{78}$Ni and $^{100}$Sn have provided benchmark studies of the nuclear shell model for protons in the $\{0f_{5/2}, 1p_{3/2}, 1p_{1/2}, 0g_{9/2}\}$ model space. New Hamiltonians for this model space have recently been obtained based on valence-space in-medium renormalization-group (VS-IMSRG) methods with two- and three-nucleon interactions. The two-body matrix elements (TBME) obtained from these ab-initio methods served as the starting point for singular-value decomposition (SVD) method fits of the TBME to experimental binding energies and excitation energies, resulting in Hamiltonians called p35-i2, p35-i3 and p30-i3. In this paper, magnetic moments, quadrupole moments, $B(M1)$ and $B(E2)$ values obtained with these Hamiltonians are presented and compared to experiment. Results obtained from various Hamiltonians are compared to assess the theoretical uncertainties.