Isospin-breaking two-nucleon force with explicit Delta-excitations

TL;DR

This paper investigates how explicit Delta excitations influence isospin-breaking effects in the two-nucleon two-pion exchange potential within chiral effective field theory, highlighting the role of delta mass splittings in charge symmetry breaking.

Contribution

It introduces explicit Delta degrees of freedom into the analysis of isospin-breaking two-nucleon forces, revealing their significant impact on charge symmetry breaking potentials.

Findings

Delta mass splittings contribute notably to charge symmetry breaking

Delta effects oppose nucleon mass splitting effects

Explicit Delta inclusion refines understanding of isospin-breaking forces

Abstract

We study the leading isospin-breaking contributions to the two-nucleon two-pion exchange potential due to explicit Delta degrees of freedom in chiral effective field theory. In particular, we find important contributions due to the delta mass splittings to the charge symmetry breaking potential that act opposite to the effects induced by the nucleon mass splitting.