Intrinsic k_T and soft gluons in Monte Carlo event generators

2025/11/28 by Moureaux, Louis, Lelek, Aleksandra, Hautmann, Francesco +1
#FOS: Physical sciences #High Energy Physics - Phenomenology (hep-ph)

paper · doi:10.48550/arxiv.2511.23291

Abstract

Experimental measurements of the transverse momentum of Drell-Yan lepton pairs are sensitive to non-perturbative physics associated with the intrinsic parton transverse momentum k_T. We discuss recent determinations of intrinsic k_T in the context of transverse momentum dependent (TMD) parton branching calculations and collinear parton-shower Monte Carlo generators. We illustrate the influence of the soft-gluon resolution scale and the non-perturbative Sudakov region on the intrinsic k_T extraction. We emphasize the relevance of the correct treatment of correlated uncertainties between different transverse momentum bins in TMD fits and present an application to the determination of the intrinsic k_T in the forward rapidity region.

Related

• The role of the intrinsic-k_{\rm T} and soft gluon contributions in Drell-Yan production
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