Next-to-Leading-Order Predictions fort-Channel Single-Top Production at Hadron Colliders

We present the predictions at next-to-leading order (NLO) in the strong coupling for the single-top cross section in the t channel at the Tevatron and the LHC. Our calculation starts from the 2→3 Born amplitude gq→tb̄q^', keeping the b-quark mass nonzero. A comparison is performed with a traditional NLO calculation of this channel based on the 2→2 Born process with a bottom quark in the initial state. In particular, the effect of using kinematic approximations and resumming logarithms of the form log(Q²/mb²) in the 2→2 process is assessed. Our results show that the 2→3 calculation is very well behaved and in substantial agreement with the predictions based on the 2→2 process.