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arXiv · 0903.0005

Next-to-leading-order predictions for t-channel single-top production at hadron colliders

John M. Campbell·Rikkert Frederix·Fabio Maltoni·Francesco Tramontano
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Abstract

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 g q -> t bbar q', keeping the b-quark mass non-zero. 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(Q^2/m_b^2) 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.

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John M. Campbell, Rikkert Frederix, Fabio Maltoni, Francesco Tramontano. 2009-05-01. Next-to-leading-order predictions for t-channel single-top production at hadron colliders. https://doi.org/10.1103/physrevlett.102.182003

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