The qT and ∆ϕ spectra in W and Z production at the LHC at N3LL′+N2LO

Ju, Wan-Li; Schönherr, Marek

Abstract

The production of weak gauge bosons, W± and Z, are at the core of the LHC precision measurement program. Their transverse momentum spectra as well as their pairwise ratios are key theoretical inputs to many high-precision analyses, ranging from the W mass measurement to the determination of parton distribution functions. Owing to the different properties of the W and Z boson and the different accessible fiducial regions for their measurement, a simple one-dimensional correlation is insufficient to capture the differing vector and axial-vector dynamics of the produced lepton pair. We propose to correlate them in two observables, the transverse momentum qT of the lepton pair and its azimuthal separation . Both quantities are purely transverse and therefore accessible in all three processes, either directly or by utilising the missing transverse momentum of the event. We calculate all the single-differential qT and as well as the double-differential (qT ,) spectra for all three processes at N3LL0+N2LO accuracy, resumming small transverse momentum logarithms in the soft-collinear effective theory approach and including all singlet and non-singlet contributions. Using the double-differential cross sections we build the pairwise ratios RW+/Z, RW−/Z, and RW+/W− and determine their uncertainties assuming fully correlated, partially correlated, and uncorrelated uncertainties in the respective numerators and denominators. In the preferred partially correlated case we find uncertainties of less than 1% in most phase space regions and up to 3% in the lowest qT region.

Citation

Ju, W.-L., & Schönherr, M. (2021). The qT and ∆ϕ spectra in W and Z production at the LHC at N3LL′+N2LO. Journal of High Energy Physics, 2021(10), https://doi.org/10.1007/jhep10%282021%29088

• Journal Article Type: Article
• Acceptance Date: Sep 21, 2021
• Online Publication Date: Oct 12, 2021
• Publication Date: 2021
• Deposit Date: Jan 11, 2022
• Publicly Available Date: Jan 11, 2022
• Journal: Journal of High Energy Physics
• Print ISSN: 1126-6708
• Electronic ISSN: 1029-8479
• Publisher: Scuola Internazionale Superiore di Studi Avanzati (SISSA)
• Peer Reviewed: Peer Reviewed
• Volume: 2021
• Issue: 10
• DOI: https://doi.org/10.1007/jhep10%282021%29088
• Public URL: https://durham-repository.worktribe.com/output/1218281