We report the top quark mass measurement with DLM (Dynamical Likelihood Method) in the Top dilepton channel by using the CDF Run
II detector at the Fermilab Tevatron Collider. For each event, the parton level kinematics is reconstructed by generating (a) the invariant mass squares for $t$, $\bar{t}$ and $W^{\pm}$, (b) the $b$-quark energies and (c)the sum of the neutrino transverse momentum. The generating functions for (a) are propagator factors, and those for (b) and (c) are transfer functions. The differential cross-section at the parton level is used to define the likelihood of the reconstructed kinematics as a function of the top quark mass. The likelihood in an event is summed up, and the event likelihoods are multiplied each other to get the mass joint likelihood. The maximum likelihood estimate and its uncertainty was obtained by the standard treatment. The Monte Calro Generator HERWIG with $M_t = 178$ GeV/$c^{2}$ Top Mass Sample was used to validate the method, and we expect a statistical uncertainty of +7.3 - 6.7 GeV/$c^{2}$ and a systematic uncertainty of 3.2 GeV/$c^{2}$. By using the 32 events observed with $\int Ldt = 340.5 \mathrm{pb}^{-1}$ of data, we measured the top quark mass of 166.6 GeV/$c^2$.


Posted to /cdf/pub/thesis/cdf8283_thesis.ps
    http://www-cdf.fnal.gov/thesis/cdf8283_thesis.ps

Posted by ryo