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arXiv · 2312.05203

Non-Relativistic Quantum Chromodynamics in Parton Showers

Naomi Cooke·Philip Ilten·Leif Lönnblad·Stephen Mrenna
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Abstract

Measurements of quarkonia isolation in jets at the Large Hadron Collider (LHC) have been shown to disagree with fixed-order non-relativistic quantum chromodynamics (NRQCD) calculations, even at higher orders. Calculations using the fragmenting jet function formalism are able to better describe data but cannot provide full event-level predictions. In this work we provide an alternative model via NRQCD production of quarkonia in a timelike parton shower. We include this model in the Pythia 8 event generator and validate our parton-shower implementation against analytic forms of the relevant fragmentation functions. Finally, we make inclusive predictions of quarkonia production for the decay of the standard-model Higgs boson.

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Naomi Cooke, Philip Ilten, Leif Lönnblad, Stephen Mrenna. 2023-12-08. Non-Relativistic Quantum Chromodynamics in Parton Showers. https://arxiv.org/abs/2312.05203

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