Search for non-standard model top antitop resonance production in the all-hadronic channel at CDF

We present the first result of a novel search for resonant top-antitop pair production and subsequent decay in the all-hadronic channel. We examine the top-antitop invariant mass spectrum observed in CDF II data from 1.9 TeV proton-antiproton collisions at Fermilab Tevatron. A narrow resonance state decaying to a top-antitop pairs will appear as a ``bump'' in the observed mass spectrum. We apply a powerful reconstruction technique where the observed event kinematics are constrained according to the full standard model top-antitop production and decay matrix element. This technique provides excellent mass resolution. Also, probability densities from the per-event matrix element calculation are used as discriminants to reduce and control the large backgrounds of the all-hadronic channel.