We present LO, NLO and NNLO sets of parton distribution functions (PDFs) of the proton determined from global analyses of the available hard scattering data. These MMHT2014 PDFs supersede the ‘MSTW2008’ parton sets, but they are obtained within the same basic framework. We include a variety of new data sets, from the LHC, updated Tevatron data and the HERA combined H1 and ZEUS data on the total and charm structure functions. We also improve the theoretical framework of the previous analysis. These new PDFs are compared to the ‘MSTW2008’ parton sets. In most cases the PDFs, and the predictions, are within one standard deviation of those of MSTW2008. The major changes are the valence quark difference at small due to an improved parameterisation and, to a lesser extent, the strange quark PDF due to the effect of certain LHC data and a better treatment of the branching ratio. We compare our MMHT PDF sets with those of other collaborations; in particular with the NNPDF3.0 sets, which are contemporary with the present analysis.

Single-top hadroproduction in association with a W bosonFrixione, S.; Laenen, E.L.M.P.; Motylinski, P.; White, C.; Webber, B.R. General rightsIt is not permitted to download or to forward/distribute the text or part of it without the consent of the author(s) and/or copyright holder(s), other than for strictly personal, individual use, unless the work is under an open content license (like Creative Commons). Disclaimer/Complaints regulationsIf you believe that digital publication of certain material infringes any of your rights or (privacy) interests, please let the Library know, stating your reasons. In case of a legitimate complaint, the Library will make the material inaccessible and/or remove it from the website. Please Ask the Library: http://uba.uva.nl/en/contact, or a letter to: Library of the University of Amsterdam, Secretariat, Singel 425, 1012 WP Amsterdam, The Netherlands. You will be contacted as soon as possible. Abstract: We present the calculation of the W t single-top production channel to nextto-leading order in QCD, interfaced with parton showers within the MC@NLO formalism. This channel provides a complementary way of investigating the properties of the W tb vertex, with respect to the s-and t-channels. We pay special attention to the separation of this process from top quark pair production.

We match next-to-leading order QCD results for single-top hadroproduction with parton shower Monte Carlo simulations, according to the prescription of the MC@NLO formalism. In this way, we achieve the first practical implementation in MC@NLO of a process that has both initial-and final-state collinear singularities. We show that no difficulties of principle arise from this complication, and present selected results relevant to the Tevatron.

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We explain how angular correlations in leptonic decays of vector bosons and top quarks can be included in Monte Carlo parton showers, in particular those matched to NLO QCD computations. We consider the production of n pairs of leptons, originating from the decays of n electroweak vector bosons or of n top quarks, in the narrow-width approximation. In the latter case, the information on the n b quarks emerging from the decays is also retained. We give results of implementing this procedure in MC@NLO.