Applications of reduced basis methods to the nuclear single particle spectrum

TL;DR

This paper introduces a reduced basis emulator for nuclear single-particle spectra, achieving high accuracy across various nuclei, which could enhance future nuclear modeling and calibration methods.

Contribution

It presents the first application of reduced basis methods to nuclear physics, creating a universal emulator for single-particle spectra that is both accurate and efficient.

Findings

Accurately reproduces ground- and excited-state energies

Constructs a universal reduced basis for various nuclei

Facilitates efficient Bayesian calibration of nuclear models

Abstract

Reduced basis methods provide a powerful framework for building efficient and accurate emulators. Although widely applied in many fields to simplify complex models, reduced basis methods have only been recently introduced into nuclear physics. In this letter we build an emulator to study the single-particle structure of atomic nuclei. By scaling a suitable mean-field Hamiltonian, a "universal" reduced basis is constructed capable of accurately and efficiently reproduce the entire single-particle spectrum of a variety of nuclei. Indeed, the reduced basis model reproduces both ground- and excited-state energies as well as the associated wave-functions with remarkable accuracy. Our results bode well for more demanding applications that use Bayesian optimization to calibrate nuclear energy density functionals.