  We present a measurement of the top quark mass with t-tbar dilepton events
produced in p-pbar collisions at the Fermilab Tevatron $\sqrt{s}$=1.96 TeV and
collected by the CDF II detector. A sample of 328 events with a charged
electron or muon and an isolated track, corresponding to an integrated
luminosity of 2.9 fb$^{-1}$, are selected as t-tbar candidates. To account for
the unconstrained event kinematics, we scan over the phase space of the
azimuthal angles ($\phi_{\nu_1},\phi_{\nu_2}$) of neutrinos and reconstruct the
top quark mass for each $\phi_{\nu_1},\phi_{\nu_2}$ pair by minimizing a
$\chi^2$ function in the t-tbar dilepton hypothesis. We assign
$\chi^2$-dependent weights to the solutions in order to build a preferred mass
for each event. Preferred mass distributions (templates) are built from
simulated t-tbar and background events, and parameterized in order to provide
continuous probability density functions. A likelihood fit to the mass
distribution in data as a weighted sum of signal and background probability
density functions gives a top quark mass of
$165.5^{+{3.4}}_{-{3.3}}$(stat.)$\pm 3.1$(syst.) GeV/$c^2$.
