Parton distribution functions, α s , and heavy-quark masses for LHC Run II

We determine a new set of parton distribution functions (ABMP16), the strong coupling constant ${ensuremath{alpha}}_{s}$ and the quark masses ${m}_{c}$, ${m}_{b}$ and ${m}_{t}$ in a global fit to next-to-next-to-leading order (NNLO) in QCD. The analysis uses the $overline{mathrm{MS}}$ scheme for ${ensuremath{alpha}}_{s}$ and all quark masses and is performed in the fixed-flavor number scheme for ${n}_{f}=3$, 4, 5. Essential new elements of the fit are the combined data from HERA for inclusive deep-inelastic scattering (DIS), data from the fixed-target experiments NOMAD and CHORUS for neutrino-induced DIS, data from Tevatron and the LHC for the Drell-Yan process and the hadro-production of single-top and top-quark pairs. The theory predictions include new improved approximations at NNLO for the production of heavy quarks in DIS and for the hadro-production of single-top quarks. The description of higher twist effects relevant beyond the leading twist collinear factorization approximation is refined. At NNLO, we obtain the value ${ensuremath{alpha}}_{s}^{({n}_{f}=5)}({M}_{Z})=0.1147ifmmodepmelsetextpmfi{}0.0008$.