I report on preliminary measurements of the tt̄ production cross section, and a measurement of the top quark mass, performed by the DØ Collaboration. The cross section is measured using candidates for dilepton, single‐lepton, and all‐hadronic tt̄ decays collected at DØ during RunII of the Tevatron. The results for the various modes are:
The mass measurement uses an improved method to re‐analyze lepton+jets events collected during RunI of the Tevatron, and obtains mt = 180.1 ± 3.6 (stat.) ± 4.0 (syst.) GeV/c2.