Finite amplitude method for the quasi-particle-random-phase approximation

TL;DR

This paper introduces the finite amplitude method (FAM) for superfluid systems, enabling efficient and accurate QRPA calculations by modifying existing Hartree-Fock-Bogoliubov codes, demonstrated on neutron-rich tin nucleus 174Sn.

Contribution

The paper presents a novel application of FAM to superfluid systems, simplifying QRPA computations and improving computational efficiency.

Findings

FAM accurately reproduces QRPA results for 174Sn

FAM reduces computational cost compared to traditional QRPA

FAM is easily implemented in existing HFB codes

Abstract

We present the finite amplitude method (FAM) for superfluid systems. A Hartree-Fock-Bogoliubov code may be transformed into a code of the quasi-particle-random-phase approximation (QRPA) with simple modifications. This technique has advantages over the conventional QRPA calculations, such as coding feasibility and computational cost. We perform the fully self-consistent linear-response calculation for a spherical neutron-rich nucleus 174Sn, modifying the HFBRAD code, to demonstrate the accuracy, feasibility, and usefulness of the FAM.