Probing the Higgs coupling to top quark in events with associated Higgs production with top-anti top pair and Higgs decay in two photons

We present here the results of the first search for the associated production of the Higgs boson with a tt-bar pair, using the events where the Higgs boson decays to two photons in CMS. In order to maximize acceptance and sensitivity to such a small signal, we device two different sets of event selection criteria, optimized for leptonic and all-hadronic tt-bar decays. In the absence of a significant excess over the background-only predictions, we proceed to set an observed (expected) 95% confidence level upper limit on tt-barH production cross section times BR(H → γγ) of 5.4 (5.3) times the Standard model value using 19.6 fb-1 of 8 TeV pp collisions. (authors)