Top quark mass measurement from dilepton events at CDF II with the matrix-element method

We describe a measurement of the top quark mass using events with two charged leptons collected by the CDF II detector from p (p) over bar collisions with root s=1.96 TeV at the Fermilab Tevatron. The likelihood in top quark mass is calculated for each event by convoluting the leading order matrix element describing q (q) over bar -> t (t) over bar -> bl nu(l)(b) over barl(')nu(l) with detector resolution functions. The presence of background events in the data sample is modeled using similar calculations involving the matrix elements for major background processes. In a data sample with integrated luminosity of 340 pb(-1), we observe 33 candidate events and measure M(top)=165.2 +/- 6.1(stat.)+/- 3.4(syst.) GeV/c(2). This measurement represents the first application of this method to events with two charged leptons and is the most precise single measurement of the top quark mass in this channel. RI Ruiz, Alberto/E-4473-2011; Robson, Aidan/G-1087-2011; De Cecco, Sandro/B-1016-2012; St.Denis, Richard/C-8997-2012; Prokoshin, Fedor/E-2795-2012; Azzi, Patrizia/H-5404-2012