Measurement of the Top-Quark Mass in All-Hadronic Decays in p pbar Collisions at CDF II

Abstract

We present a measurement of the top-quark mass, $M_{\mathrm{top}}$, in the all-hadronic decay channel $t\bar{t}\to W^{+}b{W}^{-}\bar{b}\to q_1{\bar{q}}_{2}b{q}_3{\bar{q}}_4\bar{b}$. The analysis is performed using 310 pb${}^{-1}$ of $\sqrt{s}$=1.96 TeV $p\bar{p}$ collisions collected with the CDF II detector using a multi-jet trigger. The mass measurement is based on an event-by-event likelihood which depends on both the sample purity and the value of the top-quark mass, using 90 possible jet-to-parton assignments in the six-jet final state. The joint likelihood of 290 selected events yields a value of $M_{\mathrm{top}}$=177.1 $\pm$ 4.9 (stat.) $\pm$ 4.7 (syst.) GeV/$c^2$.

7 pages, 2 figures and 1 table, Submitted to Phys. Rev. Lett