The top quark pair production cross-section ${ \sigma}_{ t\bar{ t}}$ has been measured in $p\bar{ p}$ collisions at center of mass energies of 1.96 TeV using Tevatron Run 2 data. In the begining of Run 2 both CDF and D\O\ $\sigma_{ t\bar{ t}}$ measurements in the { \it dilepton} channel $t\bar{ t}{ \to}WbW\bar{ b}{ \to}\bar{ \ell}{ \nu}_{ \ell}b{ \ell}^{ '}\ bar{ \nu}_{ { \ell}^{ '}}\bar{ b}$ and in the { \it lepton plus jets} channel $t\bar{ t}{ \to}WbW\bar{ b}{ \to}q\bar{ q}^{ '}b{ \ell}\bar{ \nu}_{ \ell }\bar{ b}+\bar{ \ell}{ \nu}_{ \ell}bq\bar{ q}^{ '}\bar{ b}$ agree with the NLO (Next-to-Leading-Order) theoretical predictions. The presence of a top signal in Tevatron data has been reestablished.
Categories: hep-ex