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arXiv · 2008.00342

HQET vertex diagram: $\varepsilon$ expansion

A. G. Grozin
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Abstract

Differential equations for the one-loop HQET vertex diagram with arbitrary self-energy insertions and arbitrary residual energies are reduced to the $\varepsilon$ form and used to obtain the $\varepsilon$ expansion in terms of Goncharov polylogarithms.

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A. G. Grozin. 2020-08-01. HQET vertex diagram: $\varepsilon$ expansion. https://doi.org/10.1103/physrevd.102.054022

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