Abstract

The accurate determination of Parton Distribution Functions (PDFs) of the proton is a crucial ingredient for the physics program of the LHC. PDFs are one of the most important sources of theoretical uncertainty in the predictions for Higgs boson production, induce large uncertainties for high-mass New Physics particle production and they affect precision SM measurements such as the mass of the W boson and the effective lepton mixing angle. For these reasons, an active program towards better PDFs is being carried out by different groups, based on using new experimental inputs, more accurate theoretical calculations and on improving the fitting methodology. In this talk I present the new generation of PDF sets based on the NNPDF methodology, and study some of their phenomenology at LHC Run II, including their role for Higgs coupling determinations, precision predictions for high-mass SUSY production using threshold resummation, implications of LHC charm data for neutrino astronomy, and PDFs for electroweak calculations.