Dominant mixed QCD-electroweakO(αsα)corrections to Drell–Yan processes in the resonance region

Abstract

A precise theoretical description of W-and Z-boson production in the resonance region is essential for the correct interpretation of high-precision measurements of the W-boson mass and the effective weak mixing angle. Currently, the largest unknown fixed-order contribution is given by the mixed QCD-electroweak corrections of O(α s α). We argue, using the framework of the pole expansion for the NNLO QCD-electroweak corrections established in a previous paper, that the numerically dominant corrections arise from the combination of large QCD corrections to the production with the large electroweak corrections to the decay of the W/Z boson. We calculate these so-called factorizable corrections of "initial-final" type and estimate the impact on the W-boson mass extraction. We compare our results to simpler approximate combinations of electroweak and QCD corrections in terms of naive products of NLO QCD and electroweak correction factors and using leading-logarithmic approximations for QED final-state radiation as provided by the structure-function approach or QED parton-shower programs. We also compute corrections of "final-final" type, which are given by finite counterterms to the leptonic vectorboson decays and are found to be numerically negligible.

Two-loop master integrals for the mixed EW-QCD virtual corrections to Drell-Yan scattering

“…In [79], the mixed two-loop corrections to the form factors for the production of a Z boson were calculated analytically, expressing the result in terms of harmonic polylogarithms and related generalizations. In [80], the authors calculated the mixed corrections in the pole approximation near the resonance region. In particular, they worked out in this region three different contributions.…”

“…These last contributions are suppressed way below the percent level and they are negligible for the curent phenomenological purposes. In [81], the mixed αα S…”

Heavy Higgs boson resonances and their decay into top quarks at the LHC

“…The former are manifestly resonant while the latter consist of resonant and non-resonant contributions. The resonant parts of the non-factorizable contributions can be extracted by applying the soft gluon approximation [15,16,17,18]. Within this approximation non-factorizable contributions from the real and virtual corrections cancel exactly.…”

Double-real corrections at $${{\mathcal {O}}(\alpha \alpha _s)}\,$$to single gauge boson production

“…[61][62][63]. The calculation was done in the pole approximation, namely retaining all the leading terms contributing to the W (Z ) boson resonance.…”