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arXiv · hep-ph/0307295

QED vertex form factors at two loops

R. Bonciani·P. Mastrolia·E. Remiddi
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Abstract

We present the closed analytic expression of the form factors of the two-loop QED vertex amplitude for on-shell electrons of finite mass $m$ and arbitrary momentum transfer $S=-Q^2$. The calculation is carried out within the continuous $D$-dimensional regularization scheme, with a single continuous parameter $D$, the dimension of the space-time, which regularizes at the same time UltraViolet (UV) and InfraRed (IR) divergences. The results are expressed in terms of 1-dimensional harmonic polylogarithms of maximum weight 4.

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R. Bonciani, P. Mastrolia, E. Remiddi. 2003-07-23. QED vertex form factors at two loops. https://doi.org/10.1016/j.nuclphysb.2003.10.031

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