Magnetic effects of QCD parameters from finite energy sum rules

TL;DR

This paper uses finite energy sum rules to study how external magnetic fields influence key QCD parameters like quark masses, pion properties, and condensates, revealing their magnetic evolution.

Contribution

It applies finite energy sum rules to analyze the magnetic dependence of various QCD and hadronic parameters in the light quark sector, combining axial and pseudoscalar channels.

Findings

Magnetic evolution of light quark masses

Magnetic dependence of pion mass and decay constant

Changes in gluon condensate and hadronic threshold

Abstract

One of the advantages of the finite energy sum rules is the fact that every operator in the operator product expansion series can be selected individually by the use of an appropriate kernel function which removes other operator poles. This characteristic is maintained by QCD systems in the presence of external homogeneous magnetic field, providing interesting information about the magnetic evolution of QCD and hadronic parameters. In this work finite energy sum rules are applied on QCD in the light quark sector, combining axial and pseudoscalar channels in the presence of an external homogeneous magnetic field, obtaining the magnetic evolution of the light quark masses, pion mass, the pion decay constant, the gluon condensate and the continuum hadronic threshold.