The LbL contribution to the muon g-2 from the axial-vector mesons exchanges within the nonlocal quark model

A.E Dorokhov,A.E Radzhabov,A.S Zhevlakov,A.P Martynenko,F.A Martynenko

doi:10.1051/epjconf/201921205001

Abstract

The light-by-light contribution from the axial-vector (AV) mesons exchanges to the muon anomalous magnetic moment is estimated in the framework of the nonlocal chiral quark model. The preliminary answer for contributions from a1 and f1 mesons to (g − 2)µ is 0.34 · 10−11 and does not support the Melnikov-Vainshtein estimate 2.2 · 10−11.

Highlights

It is interesting to note that in [4] is shown that the axial-vector exchange interaction in muonic hydrogen gives essential contribution to hyperfine splitting
For hyperfine splitting the axial-vector contribution is even bigger than the pion one [5]
The presence of the longitudinal component of axial-vector mesons leads to modification of the pion vertex as

Summary

Introduction

It is interesting to note that in [4] is shown that the axial-vector exchange interaction in muonic hydrogen gives essential contribution to hyperfine splitting. For hyperfine splitting the axial-vector contribution is even bigger than the pion one [5]. For these purposes we consider the S U(2) × S U(2) chiral quark model where the pseudoscalar–scalar and vector–axial-vector sectors are included. The presence of the longitudinal component of axial-vector mesons leads to modification of the pion vertex as

Results

Conclusion