Measurement of the cross section for top quark pair production in association with a W or Z boson in proton-proton collisions at $\sqrt{s} =$ 13 TeV

Bakhshiansohi, Hamed;Bondu, Olivier;Brochet, Sébastien;Bruno, Giacomo;CMS Collaboration;et.al.
(2018) Journal of High Energy Physics — Vol. 1808, p. 11 (2018)

Files

scoap3-fulltext.pdf
  • Open Access
  • Adobe PDF
  • 1.52 MB

Details

Authors
  • Bakhshiansohi, HamedUCLouvain
    Author
  • Bondu, OlivierUCLouvain
    Author
  • Brochet, SébastienUCLouvain
    Author
  • Author
  • Caputo, ClaudioUCLouvain
    Author
  • Caudron, AdrienUCLouvain
    Author
  • David, PieterUCLouvain
    Author
  • De Visscher, SimonUCLouvain
    Author
  • Author
  • Delcourt, MartinUCLouvain
    Author
  • Author
  • Author
  • Komm, MatthiasUCLouvain
    Author
  • Krintiras, GeorgiosUCLouvain
    Author
  • Author
  • Magitteri, AlessioUCLouvain
    Author
  • Mertens, AlexandreUCLouvain
    Author
  • Musich, MarcoUCLouvain
    Author
  • Piotrzkowski, KrzysztofUCLouvain
    Author
  • Author
  • Saggio, AlessiaUCLouvain
    Author
  • Vidal Marono, MiguelUCLouvain
    Author
  • Wertz, SébastienUCLouvain
    Author
  • Zobec, JozeUCLouvain
    Author
  • CMS Collaboration
    Author
  • et. al.
Show more
Abstract
A measurement is performed of the cross section of top quark pair production in association with a W or Z boson using proton-proton collisions at a center-of-mass energy of 13 TeV at the LHC. The data sample corresponds to an integrated luminosity of 35.9 fb$^{-1}$, collected by the CMS experiment in 2016. The measurement is performed in the same-sign dilepton, three- and four-lepton final states. The production cross sections are measured to be $\sigma(\mathrm{t}\overline{\mathrm{t}}\mathrm{W})= 0.77 ^{+0.12}_{-0.11}\text{(stat)} ^{+0.13}_{-0.12}\text{(syst)}$ pb and $\sigma(\mathrm{t}\overline{\mathrm{t}}\mathrm{Z}) = 0.99 ^{+0.09}_{-0.08}\text{(stat)} ^{+0.12}_{-0.10}\text{(syst)}$ pb. The expected (observed) signal significance for the $\mathrm{t}\overline{\mathrm{t}}\mathrm{W}$ production in same-sign dilepton channel is found to be 4.5 (5.3) standard deviations, while for the $\mathrm{t}\overline{\mathrm{t}}\mathrm{Z}$ production in three- and four-lepton channels both the expected and the observed significances are found to be in excess of 5 standard deviations. The results are in agreement with the standard model predictions and are used to constrain the Wilson coefficients for eight dimension-six operators describing new interactions that would modify $\mathrm{t}\overline{\mathrm{t}}\mathrm{W}$ and $\mathrm{t}\overline{\mathrm{t}}\mathrm{Z}$ production.
Affiliations

Citations

Bakhshiansohi, H., Bondu, O., Brochet, S., Bruno, G., Caputo, C., Caudron, A., David, P., De Visscher, S., Delaere, C., Delcourt, M., François, B., Giammanco, A., Komm, M., Krintiras, G., Lemaitre, V., Magitteri, A., Mertens, A., Musich, M., Piotrzkowski, K., et al. (2018). Measurement of the cross section for top quark pair production in association with a W or Z boson in proton-proton collisions at $\sqrt{s} =$ 13 TeV. Journal of High Energy Physics, 1808, 11. https://doi.org/10.1007/JHEP08(2018)011 (Original work published 2018)