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arXiv · 2108.10024

Tagging the initial-state gluon

Abstract

We study the production of an electroweak boson in association with jets, in processes where the jet with the highest transverse momentum is identified as quark-initiated. The quark/gluon tagging procedure is realised by a cut on a jet angularity and it is therefore theoretically well-defined and exhibits infrared and collinear safety. In this context, exploiting resummed perturbation theory, we are able to provide theoretical predictions for transverse momentum distributions at a well-defined and, in principle, systematically improvable accuracy. In particular, tagging the leading jet as quark-initiated allows us to enhance the initial-state gluon contribution. Thus, these novel transverse momentum distributions are potentially interesting observables to probe the gluonic degrees of freedom of the colliding protons.

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Simone Caletti, Oleh Fedkevych, Simone Marzani, Daniel Reichelt. 2021-08-23. Tagging the initial-state gluon. https://doi.org/10.1140/epjc/s10052-021-09648-x

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