  We present NNPDF3.0, the first set of parton distribution functions (PDFs)
determined with a methodology validated by a closure test. NNPDF3.0 uses a
global dataset including HERA-II deep-inelastic inclusive cross-sections, the
combined HERA charm data, jet production from ATLAS and CMS, vector boson
rapidity and transverse momentum distributions from ATLAS, CMS and LHCb, W+c
data from CMS and top quark pair production total cross sections from ATLAS and
CMS. Results are based on LO, NLO and NNLO QCD theory and also include
electroweak corrections. To validate our methodology, we show that PDFs
determined from pseudo-data generated from a known underlying law correctly
reproduce the statistical distributions expected on the basis of the assumed
experimental uncertainties. This closure test ensures that our methodological
uncertainties are negligible in comparison to the generic theoretical and
experimental uncertainties of PDF determination. This enables us to determine
with confidence PDFs at different perturbative orders and using a variety of
experimental datasets ranging from HERA-only up to a global set including the
latest LHC results, all using precisely the same validated methodology. We
explore some of the phenomenological implications of our results for the
upcoming 13 TeV Run of the LHC, in particular for Higgs production
cross-sections.
