Next-to-leading order corrections to Wt production and decay

John Campbell; Francesco Tramontano

doi:10.1016/j.nuclphysb.2005.08.015

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arXiv · hep-ph/0506289

Next-to-leading order corrections to Wt production and decay

John Campbell·Francesco Tramontano

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Abstract

We present the results of a next-to-leading order calculation of Wt production, including the decays of both the top quark and the W boson. The effects of radiation in the decay of the top quark are also included. The separation of diagrams which appear in the real corrections, into singly- and doubly-resonant contributions, is performed using a b-jet veto which is motivated by the use of the bottom quark distribution function. We find that, for a choice of scale which is suitable for this approach, the QCD corrections are very mild and only change the cross section by up to 10% at the LHC, depending on the severity of the b-jet veto. When further cuts are applied, applicable for a Higgs boson search in the H->WW channel, we find that the radiative effects greatly decrease the number of background events expected from this process. In addition, the shapes of relevant distributions can be significantly changed at next-to-leading order.

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John Campbell, Francesco Tramontano. 2005-06-28. Next-to-leading order corrections to Wt production and decay. https://doi.org/10.1016/j.nuclphysb.2005.08.015

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