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arXiv · 1510.07012

Gauge-invariant field-strength correlators for QCD in a magnetic background

Massimo D'Elia·Enrico Meggiolaro·Michele Mesiti·Francesco Negro
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Abstract

We consider the properties of the gauge-invariant two-point correlation functions of the gauge-field strengths for QCD in the presence of a magnetic background field. We discuss the general structure of the correlators in this case and provide the results of an exploratory lattice study for $N_f = 2$ QCD discretized with unimproved staggered fermions. Our analysis provides evidence for the emergence of anisotropies in the non-perturbative part of the correlators and for an increase of the gluon condensate as a function of the external magnetic field.

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Massimo D'Elia, Enrico Meggiolaro, Michele Mesiti, Francesco Negro. 2016-03-10. Gauge-invariant field-strength correlators for QCD in a magnetic background. https://doi.org/10.1103/physrevd.93.054017

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