Combination of the W boson polarization measurements in top quark decays using ATLAS and CMS data at √s = 8 TeV

The ATLAS collaboration, The ATLAS collaboration, The ATLAS collaboration, The ATLAS collaboration, The ATLAS collaboration, The CMS collaboration, The CMS collaboration, The ATLAS collaboration, The ATLAS collaboration, The ATLAS collaboration

Research output: Contribution to journalArticlepeer-review

25 Scopus citations

Abstract

The combination of measurements of the W boson polarization in top quark decays performed by the ATLAS and CMS collaborations is presented. The measurements are based on proton-proton collision data produced at the LHC at a centre-of-mass energy of 8 TeV, and corresponding to an integrated luminosity of about 20 fb−1 for each experiment. The measurements used events containing one lepton and having different jet multiplicities in the final state. The results are quoted as fractions of W bosons with longitudinal (F0), left-handed (FL), or right-handed (FR) polarizations. The resulting combined measurements of the polarization fractions are F0 = 0.693 ± 0.014 and FL = 0.315 ± 0.011. The fraction FR is calculated from the unitarity constraint to be FR = −0.008 ± 0.007. These results are in agreement with the standard model predictions at next-to-next-to-leading order in perturbative quantum chromodynamics and represent an improvement in precision of 25 (29)% for F0 (FL) with respect to the most precise single measurement. A limit on anomalous right-handed vector (VR), and left- and right-handed tensor (gL, gR) tWb couplings is set while fixing all others to their standard model values. The allowed regions are [−0.11, 0.16] for VR, [−0.08, 0.05] for gL, and [−0.04, 0.02] for gR, at 95% confidence level. Limits on the corresponding Wilson coefficients are also derived. [Figure not available: see fulltext.]

Original languageEnglish
Article number51
JournalJournal of High Energy Physics
Volume2020
Issue number8
DOIs
StatePublished - 1 Aug 2020

Keywords

  • Hadron-Hadron scattering (experiments)
  • Top physics

Fingerprint

Dive into the research topics of 'Combination of the W boson polarization measurements in top quark decays using ATLAS and CMS data at √s = 8 TeV'. Together they form a unique fingerprint.

Cite this