Measurement of t-channel single top quark production at 7 TeV

A first measurement of the cross section of single top quark production in the $t$ channel in pp collision at $\sqrt{s}=7$ TeV is presented. The measurement is performed on a data sample corresponding to an integrated luminosity of 35.9 pb$^{-1}$ recorded at the LHC with the CMS detector. Leptonic decay channels with an electron or a muon in the final state are considered. After a selection optimized for the $t$-channel mode, two different and complementary analyses have been performed. Both analyses confirm the Tevatron's observation of single top, and their combination measures a cross section of $\sigma = 83.6 \pm 29.8~\mathrm{(stat.+syst.)} \pm 3.3~\mathrm{(lumi.)\,\,pb}$ which is consistent with the Standard Model prediction.