Transverse-momentum resummation: a perturbative study of Z production at the Tevatron

TL;DR

This paper develops a method for resumming logarithmic QCD contributions in Z boson production at the Tevatron, combining resummed and fixed-order calculations to improve predictions of transverse momentum distributions.

Contribution

It provides a next-to-leading logarithmic resummation framework for Z production that is matched with fixed-order results, enhancing the accuracy of transverse momentum predictions.

Findings

Resummation improves agreement with Tevatron data.

Scale dependence analysis estimates theoretical uncertainties.

The combined approach covers small to large q_T regions effectively.

Abstract

We consider transverse-momentum (q_T) resummation for Drell--Yan lepton pair production in hadron collisions. At small values of q_T, the logarithmically-enhanced QCD contributions are resummed up to next-to-leading logarithmic accuracy. At intermediate and large values of q_T, resummation is consistently combined with the fixed-order perturbative result. We present numerical results for e^+e^- pairs from the decay of Z bosons produced at Tevatron energies. We perform a detailed study of the scale dependence of the results to estimate the corresponding perturbative uncertainty. We comment on the comparison with the available Tevatron data.