Isospinning Skyrmions

TL;DR

This paper investigates how classical Skyrmion solutions deform under isospin and spin, aiming to improve the modeling of atomic nuclei beyond the rigid body approximation in the Skyrme model.

Contribution

It introduces the study of Skyrmion deformations due to isospin and spin, moving beyond the rigid body approximation to better match nuclear physics data.

Findings

Skyrmions deform when classical isospin is added

Deformations depend on topological charge

Potential for improved nuclear modeling

Abstract

In the Skyrme model atomic nuclei are modelled as quantized soliton solutions in a nonlinear field theory of pions. The mass number is given by the conserved topological charge $B$ of the solitons. Conventionally, Skyrmions are semiclassically quantized within the rigid body approach. In this approach Skyrmions are effectively treated as rigid rotors in space and isospace that is it is assumed that Skyrmions do not deform at all when they spin and isospin. This approximation resulted in qualitative and encouraging quantitative agreement with experimental nuclear physics data. In this talk, we point out that the theoretical agreement could be further improved by allowing classical Skyrmion solutions to deform as they spin and isospin. As a first step towards a better understanding of how nuclei can be approximated by classically spinning and isospinning soliton solutions, we study how classical Skyrmion solutions of topological charges $B=1-4,8$ deform when classical isospin is added.