Abstract
We consider transverse-momentum resummation for top-quark pair production in hadron collisions. At small transverse momenta of the top-quark pair, the logarithmically-enhanced QCD contributions are resummed to all orders up to next-to-leading logarithmic accuracy. At intermediate and large values of transverse momenta, the resummation is consistently combined with the complete result at fixed perturbative order. We present numerical results for the transverse-momentum distribution of top-quark pairs at LHC energies. We perform a detailed study of the scale dependence of the results to estimate their perturbative uncertainty. We comment on the comparison with ATLAS and CMS data.
Highlights
This type of perturbative behaviour at small qT is well known [29,30,31,32] from the hadroproduction process of a high-mass lepton pair through the Drell-Yan (DY) mechanism
An independent formulation of transverse-momentum resummation for heavy-quark pairs, including the complete treatment of azimuthal correlations is presented in ref
We present the numerical results of our calculation and we compare them to ATLAS and CMS Run 1 data
Summary
The resummation formalism that we use in this paper is discussed in detail in ref. [38]. Since the factor HN in eq (2.4) does not contain logarithmically-enhanced contributions, we treat it by truncation of the perturbative expansion in eq (2.7) at a given fixed-order accuracy, analogously to the treatment of the regular component dσ(reg) of the cross section in eq (2.2). In the case of ttproduction the functions gN(2), gN(3) and so forth have an additional component [36,37,38] due to soft-parton radiation at wide angles with respect to the direction of the colliding partons (hadrons) This component is produced by the non-vanishing colour charge of t and tand, as recalled, it embodies the effect of soft radiation from the heavy-quark final state and from initial-state and finalstate interferences.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
