Abstract:
We report a measurement of the tt-bar production cross section using the CDF II detector at the Fermilab Tevatron. The analysis is performed using 322 pb-1 of p anti-p collisions at s**(1/2) = 1.96 TeV. The data consist of events selected with six or more hadronic jets with additional kinematic requirements. At least one of these jets must be identified as a b-quark jet by the reconstruction of a secondary vertex. The cross section is measured to be sigma_tt-bar = 7.5 +/- 2.1(stat.)+3.3_-2.2(syst.)+0.5_-0.4(lumi.) pb, which is consistent with the standard model prediction.