Geum Bong Yu (Seoul National University (KR))
The first result of searching for a light charged Higgs decaying to cb-bar in 8 TeV CMS data corresponding to 19.7/fb is reported. When the charged Higgs has lighter mass than the top quark mass and strongly couples to the top quark, thereby it is expected to be found in the top quark decays. The cb-bar decay has been of interest by theorist since the hadronic channel of the charged Higgs was performed. This decay mode is enhanced particularly in the Type-Y(flipped) of the 2HDM. Exploiting high purity of ttbar in the lepton+four jets channel, one top with leptonic W decay and a b-jet is taken to be the normal SM top quark decay, and the other top quark decays to a b-jet and two jets. If both top quarks decay to W and b quark in the SM, the di-jet mass distribution would have only one peak at W boson mass. However, charged Higgs, assuming B(H+ to cbbar) = 1, in top quark decays would make a second peak over the W mass. One more b quark in the charged Higgs signal is used to increase the search sensitivity by using both di-jet mass distributions in 2 b-tags and 3 b-tags simultaneously.
Arnd Meyer (Rheinisch-Westfaelische Tech. Hoch. (DE))