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arXiv · 2101.11160

QCD effects in lepton angular distributions of Drell-Yan/$Z$ production and jet discrimination

Wen-Chen Chang·Randall Evan McClellan·Jen-Chieh Peng·Oleg Teryaev
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Abstract

We present a comparison of data of lepton angular distributions of Drell-Yan/$Z$ production with the fixed-order pQCD calculations by which the baseline of pQCD effects is illustrated. As for the $Z$ production, we predict that $A_0$ and $A_2$ for $Z$ plus single gluon-jet events are very different from that of $Z$ plus single quark-jet events, allowing a new experimental tool for checking various algorithms which attempt to discriminate quark jets from gluon jets. Using an intuitive geometric approach, we show that the violation of the Lam-Tung relation, appearing at large transverse-momentum region, is attributed to the presence of a non-coplanarity effect. This interpretation is consistent with the appearance of violation beyond LO-QCD effect.

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Wen-Chen Chang, Randall Evan McClellan, Jen-Chieh Peng, Oleg Teryaev. 2021-01-27. QCD effects in lepton angular distributions of Drell-Yan/$Z$ production and jet discrimination. https://doi.org/10.22323/1.390.0465

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