Magnetic field induced anomalous pion couplings

TL;DR

This paper calculates how weak magnetic fields induce anomalous couplings between pions and constituent quarks within an effective field theory framework, revealing new interactions that vanish in vacuum and discussing their potential phenomenological significance.

Contribution

It introduces a calculation of magnetic field-induced pion-constituent quark couplings using Weinberg's large Nc Effective Field Theory, highlighting their emergence and potential phenomenological relevance.

Findings

Couplings vanish in vacuum

Magnetic fields induce scalar and vector couplings

Potential links to meson fluctuations

Abstract

Effective pion-constituent quark couplings induced by relatively weak magnetic fields are calculated in the framework based in Weinberg's large Nc Effective Field Theory. These couplings (form factors) vanish in the vacuum. In particular, single-pion couplings to a scalar and a vector constituent quark currents are investigated. These couplings might correspond to a fluctuation of the neutral pion into a scalar quark-antiquark state (meson) and to a vector meson, respectively. Some possible phenomenological implications are discussed.