Quark-photon vertex from lattice QCD in Landau gauge

Milena Leutnant; André Sternbeck

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arXiv · 1812.11131

Quark-photon vertex from lattice QCD in Landau gauge

Milena Leutnant·André Sternbeck

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Abstract

We study the nonperturbative structure of the quark-photon vertex in Landau gauge. To this end, we utilize lattice QCD data for the vector current for two mass-degenerate quark flavours and extract all longitudinal and transverse form factors of the underlying vertex for two off-shell kinematics. The momentum dependence of the form factors is compared to the solution of the inhomogeneous Bethe-Salpeter equation for the vertex in the rainbow-ladder approximation. Differences but also similarities are seen between our lattice and the truncated continuum results.

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Milena Leutnant, André Sternbeck. 2018-12-28. Quark-photon vertex from lattice QCD in Landau gauge. https://arxiv.org/abs/1812.11131

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