NNLO QCD Predictions of Charge Asymmetry Distributions for Inclusive W -Boson Hadroproduction

Higher-order QCD predictions of charge asymmetry distributions are presented for inclusive W^±+X→ l^±ν+X production in proton–proton ( pp ) collisions at 8, 13, and 14 TeV center-of-mass energies. The W boson or the decay lepton charge asymmetries constitute a direct probe of the relative u and d quark distributions in the proton as functions of the initial-state parton momentum fractions. The predictions for the charge asymmetry distributions are acquired at next-to-next-to-leading order (NNLO) accuracy in the perturbative QCD domain, exploiting several parton distribution function (PDF) models. The predicted lepton charge asymmetry distributions are justified with the 8 TeV measurements by the LHC experiments in both central and forward acceptance regions of the lepton pseudorapidities 0≤η≤ 2.4 and 2.0≤η≤ 4.25 , and are provided thoroughly for both the regions at 13 and 14 TeV pp collisions energies. Additionally, the impact of various lepton transverse momentum p^l_T thresholds on the lepton (or the W boson) charge asymmetry predictions at NNLO accuracy are presented in the fiducial region encompassing both central and forward detector acceptances of the lepton pseudorapidity 0≤η_l≤ 4.5 . The lepton and W boson charge asymmetry distributions are assessed to be in close correlation with the p^l_T threshold, where the distributions are particularly observed to be more correlated at a higher- p^l_T threshold. The W boson asymmetry distribution as a function of the W boson transverse momentum p^W_T is also presented with improved accuracy by matching the NNLO predictions to resummed logarithmic corrections. Overall, the predicted results represent a substantial contribution in the context of the high-precision phenomenological studies.