Search for a light charged Higgs boson in the decay channel H+→cs¯ in tt¯ events using pp collisions at s√=7 TeV with the ATLAS detector

Abstract

Altres ajuts: We thank CERN for the very successful operation of the LHC, as well as the support staff from our institutions without whom ATLAS could not be operated efficiently. We acknowledge the support of EPLANET, ERC and NSRF, European Union and MICINN, PIC, Spain. ; A search for a charged Higgs boson (H +) in tt¯ decays is presented, where one of the top quarks decays via t→H + b, followed by H +→ two jets (cs¯). The other top quark decays to Wb, where the W boson then decays into a lepton (e/μ) and a neutrino. The data were recorded in pp collisions at s√=7 TeV by the ATLAS detector at the LHC in 2011, and correspond to an integrated luminosity of 4.7 fb−1. With no observation of a signal, 95 % confidence level (CL) upper limits are set on the decay branching ratio of top quarks to charged Higgs bosons varying between 5 % and 1 % for H + masses between 90 GeV and 150 GeV, assuming B(H+→cs¯)=100 %.