Abstract
We present next-to-leading order (NLO) electroweak corrections to the dominant five angular coefficients parametrizing the Drell–Yan process in the Z-boson mass peak range for finite-p_T vector boson production. The results are presented differentially in the vector boson transverse momentum. The Lam–Tung violating difference A_0-A_2 is examined alongside the coefficients. A single lepton transverse momentum cut is needed in the case of electroweak corrections to avoid a double singularity in the photon induced diagrams, and the dependence on the value of this cut is examined. We compare the electroweak corrections to the angular coefficients to the NLO QCD corrections, including the single lepton cut. The size of the single lepton cut is found to affect the two coefficients A_0 and A_2 to largest extent. The relative size of the electroweak corrections to the coefficients is moderate for all single lepton cut values, and by extrapolation to the inclusive results, is moderate also for the full dilepton phase space case. However, for the Lam–Tung violation, there is a significant contribution from the electroweak corrections for low p_T of the lepton pair.
Highlights
With a new era of LHC runs lying ahead, accounting for Standard Model background signatures with great accuracy becomes increasingly important
We examined the effect of a single lepton transverse momentum cut, which is included to avoid
The relative sizes of the dependencies manifest themselves in the level of the Lam–Tung violation, for which we find an increasing violation for an increasing single lepton cut, as expected
Summary
With a new era of LHC runs lying ahead, accounting for Standard Model background signatures with great accuracy becomes increasingly important. The Drell–Yan process was examined in the parton model, and the leading order O(α2) expression for the process in terms of parton distribution functions was presented This was shortly followed by NLO QCD corrections to the process in Ref. A0 and A2 satisfy at leading order O(α2αS) the Lam–Tung relation A0 − A2 = 0 [5,6], a manifestation of the spin properties of the vector boson and the leptons Measurements of these angular coefficients have been performed previously at Tevatron [11,12], at CMS [13] and most recently at ATLAS [14].
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
