Prospects for the measurement of the single-top $t$-channel cross section in the muon channel with 200~pb$^{-1

We report on a study aiming at an early observation of single-top events produced in the $t$ channel in proton-proton collisions, at a centre-of-mass energy of $\sqrt{s} = 10$ TeV, in the decay channel $t\to bW\to b\mu\nu$. A template-fit method is proposed, that takes advantage of the spin correlations of the decay products in signal events, and appears robust against several systematic effects. This article assumes the use of 200~pb$^{-1}$ of integrated luminosity. %The systematic uncertainties considered correspond to a level of understanding of the detector as foreseen to be achieved at the time when this amount of data will be available. Under these conditions, a cross section uncertainty of $\pm 35\%$ (statistical) $\pm 14\%$ (systematic) $\pm 10\%$ (luminosity) and a sensitivity of~$2.7\sigma$ are expected, assuming the standard-model prediction of $\sigma({\rm single~top,~t~channel})=130$ pb.