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QCD Green functions in a gluon field

Paul Hoyer·Stephane Peigne
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Abstract

We formulate a dressed perturbative expansion of QCD, where the standard diagrams are evaluated in the presence of a constant external gluon field whose magnitude is gaussian distributed. The approach is Poincar{é} and gauge invariant, and modifies the usual results for hard processes only by power suppressed contributions. Long distance propagation of quarks and gluons turns out to be inhibited due to a branch point singularity instead of a pole at $p^2=0$ in the quark and gluon propagators. The dressing keeps the (massless) quarks in q qbar fluctuations of the photon at a finite distance from each other.

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Paul Hoyer, Stephane Peigne. 2004-12-23. QCD Green functions in a gluon field. https://doi.org/10.1088/1126-6708%2F2004%2F12%2F051

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