We present a preliminary set of updated NLO parton distributions. For the first time we have a quantitative extraction of the strange quark and antiquark distributions and their uncertainties determined from CCFR and NuTeV dimuon cross sections. Additional jet data from HERA and the Tevatron improve our gluon extraction. Lepton asymmetry data and neutrino structure functions improve the flavour separation, particularly constraining the down quark valence distribution.

http://inspirehep.net/record/752235/files/arXiv:0706.0456.pdf

Parton distributions for the LHC

Collider physics at the precision frontier

This Report summarizes the proceedings of the 2019 Les Houches workshop on Physics at TeV Colliders. Session 1 dealt with (I) new developments for high precision Standard Model calculations, (II) the sensitivity of parton distribution functions to the experimental inputs, (III) new developments in jet substructure techniques and a detailed examination of gluon fragmentation at the LHC, (IV) issues in the theoretical description of the production of Standard Model Higgs bosons and how to relate experimental measurements, and (V) Monte Carlo event generator studies relating to PDF evolution and comparisons of important processes at the LHC.

Les Houches 2019: Physics at TeV Colliders: Standard Model Working Group Report

This work studies the associated production of a top-quark pair with a W, Z, or Higgs boson at the LHC. Predictions for the total cross sections as well as for several differential distributions of the massive particles in the final state are provided. These predictions, valid for the LHC operating at 13 TeV, include without any approximation all the NLO electroweak and QCD contributions of O (αsαj+1) with i + j = 2, 3. In addition, the predictions presented here improve upon the NLO QCD results by adding the effects of soft gluon emission corrections resummed to next-to-next-to-leading logarithmic accuracy. The residual dependence of the predictions on scale and PDF choices is analyzed.

/pdf/top-quark-pair-hadroproduction-in-association-with-a-heavy-44t0cdzle3.pdf

Top-quark pair hadroproduction in association with a heavy boson at NLO+NNLL including EW corrections

First Observation of Elec-troweak Single Top Quark Production

This work studies the associated production of a top-quark pair with a $W$, $Z$, or Higgs boson at the LHC. Predictions for the total cross sections as well as for several differential distributions of the massive particles in the final state are provided. These predictions, valid for the LHC operating at $13$ TeV, include without any approximation all the NLO electroweak and QCD contributions of $\mathcal{O}(\alpha_s^{i} \alpha^{j+1})$ with $i+j=2,3$. In addition, the predictions presented here improve upon the NLO QCD results by adding the effects of soft gluon emission corrections resummed to next-to-next-to-leading logarithmic accuracy. The residual dependence of the predictions on scale and PDF choices is analyzed.

/pdf/top-quark-pair-hadroproduction-in-association-with-a-heavy-332o5pder8.pdf

We describe predictions for top quark pair differential distributions at hadron colliders, which combine state-of-the-art NNLO QCD calculations with double resummation at NNLL$'$ accuracy of threshold logarithms and small-mass logarithms. Numerical results are presented for the invariant mass distribution, the transverse momentum distribution as well as rapidity distributions. We further combine the NNLO+NNLL$'$ result with electroweak corrections in order to achieve state-of-the-art precision in the Standard Model. This is the first time that such a combination has appeared in the literature.

Ioannis Tsinikos

Papers

Top-quark pair hadroproduction in association with a heavy boson at NLO+NNLL including EW corrections

Top-quark pair hadroproduction in association with a heavy boson at NLO+NNLL including EW corrections

Top quark pair production at NNLO+NNLL$'$ in QCD combined with electroweak corrections