Search for H to bbar in association with a single top quark as a test of Higgs boson couplings at 13 TeV (original) (raw)

Abstract

A direct search for the production of a Higgs boson in association with a single top quark is performed. The analysis considers single top quark production either via the ttt channel or via the associated production with a W boson and uses Higgs boson decays to a bottom quark-antiquark pair and semileptonic top quark decays. Data recorded by the CMS detector in 2015 in pp collisions at a center-of-mass energy of 13,mathrmTeV13\,\mathrm{TeV}13,mathrmTeV, amounting to an integrated luminosity of about 2.3,mathrmfb−12.3\,\mathrm{fb}^{-1}2.3,mathrmfb−1, are analyzed. Upper limits in the two-dimensional plane spanned by the scaling factors for the coupling strength of the Higgs boson to top quarks and to weak gauge bosons with respect to the standard model predictions, kappatextt\kappa_\text{t}kappatextt and kappatextV\kappa_\text{V}kappatextV, are determined. The observed (expected) limit on the cross section for the production of a Higgs boson in association with a single top quark in the scenario with a negative Yukawa coupling of the top quark ($\kappa_\text{t} = -1.0$ and kappatextV=+1.0\kappa_\text{V} = +1.0kappatextV=+1.0) is 6.0 (6.4) times the predicted value. %Additionally, upper limits on a mathcalCP\mathcal{CP}mathcalCP-violating top-Yukawa coupling are estimated.