Work

Strong C P violation and large- N c spin-flavor symmetry

Year: 2025

Type: article

Abstract: We revisit the contribution of the QCD θ ¯ term to the C P -violating pion-nucleon couplings and the nucleon electric dipole moment in a combined large- N c and chiral perturbation theory framework. In particular, we approach this issue through the emergent spin-flavor symmetry of the baryon sector at large but finite N c . We obtain good agreement with previous analyses for the pion-nucleon couplings and show that the large- N c framework indicates that tree-level contributions to the electric dipole moment possibly play a dominant role. The spin-flavor symmetry also enables us to provide novel constraints on C P -violating pion- Δ couplings, as well as the Δ electric dipole moment and Δ N transition moment.

Source: Physical review. D/Physical review. D.

DOI: 10.1103/1jb4-tqpn

Author: Thomas R. Richardson

Institutions: Lawrence Berkeley National Laboratory, University of California, Berkeley

Language: English

Topic: Quantum Chromodynamics and Particle Interactions

Subfield: Nuclear and High Energy Physics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: hybrid

Funders: National Science Foundation, U.S. Department of Energy

Awards: G3177085294, Network for Neutrinos, Nuclear Astrophysics, and Symmetries