Evidence for associated production of a Higgs boson with a top quark pair in final states with electrons, muons, and hadronically decaying tau leptons at root s=13 TeV


Sirunyan A. M., Tumasyan A., Adam W., Ambrogi F., Asilar E., Bergauer T., ...More

JOURNAL OF HIGH ENERGY PHYSICS, no.8, 2018 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: Issue: 8
  • Publication Date: 2018
  • Doi Number: 10.1007/jhep08(2018)066
  • Journal Name: JOURNAL OF HIGH ENERGY PHYSICS
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Keywords: Hadron-Hadron scattering (experiments), Higgs physics, Top physics, LIKELIHOOD METHOD, MISSING MOMENTUM, CROSS-SECTION, PP COLLISIONS, SEARCH, RECONSTRUCTION, EVENTS
  • Middle East Technical University Affiliated: Yes

Abstract

Results of a search for the standard model Higgs boson produced in association with a top quark pair (t (t) over barH) in final states with electrons, muons, and hadronically decaying tau leptons are presented. The analyzed data set corresponds to an integrated luminosity of 35.9 fb(-1) recorded in proton-proton collisions at root s = 13 TeV by the CMS experiment in 2016. The sensitivity of the search is improved by using matrix element and machine learning methods to separate the signal from backgrounds. The measured signal rate amounts to 1.23(-0.43)(+0.45) times the production rate expected in the standard model, with an observed (expected) significance of 3.2 sigma (2.8 sigma), which represents evidence for t (t) over barH production in those final states. An upper limit on the signal rate of 2.1 times the standard model production rate is set at 95% confidence level.