Search for a light charged Higgs boson in the decay channel [Formula: see text] in [Formula: see text] events using...

A search for a charged Higgs boson (H⁺) in [Formula: see text] decays is presented, where one of the top quarks decays via t→H⁺b, followed by H⁺→ two jets ([Formula: see text]). 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 [Formula: see text] 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 [Formula: see text].