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arXiv · 1210.1759

The role of momentum dependent dressing functions and vector meson dominance in hadronic light-by-light contributions to the muon g-2

Tobias Goecke·Christian S. Fischer·Richard Williams
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Abstract

We present a refined calculation of the quark-loop contribution to hadronic light-by-light scatter- ing that focuses upon the impact of the transverse components of the quark-photon vertex. These structures are compared and contrasted with those found within the extended NJL-models. We discuss similarities and differences between the two approaches and further clarify the important role of momentum dependent dressing functions. As expected we find that the transverse structures of the quark-photon vertex lead to a suppression of the quark-loop contribution to the anomalous magnetic moment of the muon. However, we find evidence that this suppression is overestimated within models with simple approximations for the quark-photon interaction.

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Tobias Goecke, Christian S. Fischer, Richard Williams. 2012-10-23. The role of momentum dependent dressing functions and vector meson dominance in hadronic light-by-light contributions to the muon g-2. https://doi.org/10.1103/physrevd.87.034013

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