Combination of the W boson polarization measurements in top quark decays using ATLAS and CMS data at √s = 8 TeV
Name
Aaij2019_Article_PromPtΛcProductionInPPbCollisi.pdf
Description
Published version
Size
710.97 KB
Format
Adobe PDF
Checksum (MD5)
d7ffdf923b079f434befa8e7bf0b3fc0
Author(s)
The LHCb Collaboration
Boettcher, Thomas Julian
Craik, Daniel C
Weisser, Constantin
Williams, Michael
Date Issued
2020
Journal
Journal of High Energy Physics
Publisher
Springer Science and Business Media LLC
Citation
2020. "Combination of the W boson polarization measurements in top quark decays using ATLAS and CMS data at √s = 8 TeV." Journal of High Energy Physics, 2020 (8).
Version
Final published version
Abstract
© 2020, The Author(s). 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.]
MIT Department
Massachusetts Institute of Technology. Department of Physics
Massachusetts Institute of Technology. Laboratory for Nuclear Science
Terms of Use
Creative Commons Attribution 4.0 International license
Persistent DSpace Link
DOI of Published Version
https://doi.org/10.1007/JHEP08(2020)051
