Search for single b*-quark production with the ATLAS detector at √s = 7 TeV

The results of a search for an excited bottom-quark b in pp collisions at √s=7 TeV, using 4.7 fb−14.7 fb−1 of data collected by the ATLAS detector at the LHC are presented. In the model studied, a single b-quark is produced through a chromomagnetic interaction and subsequently decays to a W boson and a top quark. The search is performed in the dilepton and lepton + jets final states, which are combined to set limits on b⁎b⁎-quark couplings for a range of b-quark masses. For a benchmark with unit size chromomagnetic and Standard Model-like electroweak b⁎b⁎ couplings, b⁎b⁎ quarks with masses less than 870 GeV870 GeV are excluded at the 95% credibility level.