Experimental analyses of charged current deep inelastic charm production – as observed through dimuon events in neutrino-iron scattering – measure the strangeness component of the nucleon sea. A complete analysis requires a Monte Carlo simulation to account for experimental detector acceptance effects; therefore, a fully differential theoretical calculation is necessary to provide complete kine...

Neutrino induced deep inelastic charm production off strange sea partons in the nucleon is studied in the framework of the MS fixed flavor factorization scheme. The momentum (z) distributions of the produced D mesons as calculated in the next–to–leading order QCD analysis are presented and compared to their leading order counterparts. Perturbative stability within this formalism is demonstrated...

The measurement and QCD analysis of neutral and charged current cross sections at HERA are presented. For the kinematic range of four-momentum transfer Q 2 between ≈ 1 GeV 2 and 30000 GeV 2 and Bjorken x between 0.0013 and 0.65 the data are compared to NLO QCD predictions. In dedicated NLO QCD analyses the extraction of the parton distribution functions of the proton is performed. Results for t...

The measurement and QCD analysis of neutral and charged current cross sections at HERA are presented. For the kinematic range of four-momentum transfer Q 2 between ≈ 1 GeV 2 and 30000 GeV 2 and Bjorken x between 0.0013 and 0.65 the data are compared to NLO QCD predictions. In dedicated NLO QCD analyses the extraction of the parton distribution functions of the proton is performed. Results for t...

MC@NLO [2, 3] is a generator for calculating next-to-leading order matrix elements, combined with a Monte Carlo event generator. When constructing an MC@NLO one needs to match the NLO matrix element with the parton shower of the generator. If wrongfully done, some of the configurations produced by the real gluon emissions in the matrix element may also be produced by the first branching in the ...

We present updated predictions for the cross sections for pair production of squarks and gluinos at the LHC Run II. First of all, we update the calculations based on NLO+NLL partonic cross sections by using the NNPDF3.0NLO global analysis. This study includes a full characterization of theoretical uncertainties from higher orders, PDFs and the strong coupling. Then we explore the implications f...

I review progress related to the calculation of QCD jet cross sections at the NLO accuracy. After a short introduction into the theory of NLO calculations, I discuss two recent developments: the calculation of twoand three-jet leptoproduction at the NLO accuracy and the extension of the dipole subtraction method for computing NLO corrections for processes involving massive partons. Jet cross se...

Spin-dependent parton distributions in the polarized virtual photon are investigated in QCD up to the next-to-leading order (NLO). In the case Λ ≪ P 2 ≪ Q, where −Q (−P ) is the mass squared of the probe (target) photon, parton distributions can be predicted completely up to the NLO, but they are factorization-scheme-dependent. Parton distributions are analyzed in four different factorization s...

A recent global analysis of direct photon production at hadron collider and xed target experiments has noted a disturbing trend of disagreement between next-to-leading-order (NLO) calculations and data. The conjecture has been made that the discrepancy is due to explicit multiple parton emission e ects which are not accounted for in the theoretical calculations. We investigate this problem by m...

We present a brief description of the light-cone gauge calculation of the spin-dependent next-to-leading order splitting functions. It has recently become possible to perform analyses of the spin-dependent parton distributions of a longitudinally polarized hadron at next-to-leading order (NLO) accuracy of QCD. A first such phenomenological NLO study, taking into account all available experiment...