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arXiv · 2011.04701

On the non-cancellation of infrared singularities in collisions of massive quarks

Fabrizio Caola·Kirill Melnikov·Davide Napoletano·Lorenzo Tancredi
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Abstract

We discuss the infrared structure of processes with massive quarks in the initial state. It is well known that, starting from next-to-next-to-leading order in perturbative QCD, such processes exhibit a violation of the Bloch-Nordsieck theorem, in that the sum of real and virtual contributions to partonic cross sections contains uncanceled infrared singularities. The main purpose of this paper is to present a simple physical argument that elucidates the origin of these singularities and simplifies the derivation of infrared-singular contributions to heavy-quark initiated cross sections.

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Fabrizio Caola, Kirill Melnikov, Davide Napoletano, Lorenzo Tancredi. 2020-11-09. On the non-cancellation of infrared singularities in collisions of massive quarks. https://doi.org/10.1103/physrevd.103.054013

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