We have measured the top quark mass with the dynamical
likelihood method (DLM) using the CDF II detector at the 
Fermilab Tevatron.
The Tevatron produces top and anti-top pairs in $p\bar p$ 
collisions at a center-of-mass energy of 1.96 TeV. The data 
sample used in this paper was accumulated from March 2002 
through August 2003 which corresponds to an integrated 
luminosity of 162 pb$^{-1}$. We use the $t \bar t$ candidates 
in the ``lepton+jets'' decay channel with at least one $b$ tagged 
jet requirement. In DLM, the likelihood is defined as the 
differential cross section as a function of M$_{top}$ per unit 
phase space volume of the final partons, multiplied by the 
transfer function from jets to parton quantities. The method 
takes into account all possible jet combinations in an event and 
the likelihood is multiplied event by event to derive the top quark 
mass by themaximum likelihood method. Using 22 $t \bar t$ candidates 
observed in the data with 4.2 events expected from background, 
we measured the top quark mass to be 177.8 $^{+4.5}_{-5.0}$(stat.)
$\pm$ 6.2(syst.) GeV/c$^2$.


Posted to /cdf/pub/thesis/cdf7631_TopMass_LJ_dlm.ps
    http://www-cdf.fnal.gov/thesis/cdf7631_TopMass_LJ_dlm.ps

Posted by kohei