Calculation of Massive 2-Loop Operator Matrix Elements with Outer Gluon Lines

I. Bierenbaum; J. Blümlein; S. Klein

doi:10.1016/j.physletb.2007.02.059

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arXiv · hep-ph/0702265

Calculation of Massive 2-Loop Operator Matrix Elements with Outer Gluon Lines

I. Bierenbaum·J. Blümlein·S. Klein

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Abstract

Massive on-shell operator matrix elements and self-energy diagrams with outer gluon lines are calculated analytically at $O(α_s^2)$, using Mellin-Barnes integrals and representations through generalized hypergeometric functions. This method allows for a direct evaluation without decomposing the integrals using the integration-by-parts method.

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I. Bierenbaum, J. Blümlein, S. Klein. 2007-02-26. Calculation of Massive 2-Loop Operator Matrix Elements with Outer Gluon Lines. https://doi.org/10.1016/j.physletb.2007.02.059

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