Factorization of standard model cross sections at ultrahigh energy

Factorization of standard model cross sections at ultrahigh energy

Dynamical QCD Predictions for Ultrahigh Energy Neutrino Cross Sections

Neutrino-nucleon total cross sections for neutrino energies up to ultrahigh energies (UHE), Eν = 10 12 GeV, are evaluated within the framework of the dynamical (radiative) parton model. The expected uncertainties of these predictions do not exceed the level of about 20 % at the highest energies where contributions of parton distributions in the yet unmeasured region around x ≃ 10 to 10 are non-...

Ultrahigh-Energy Neutrino-Nucleon Cross Sections and Perturbative Unitarity

Unitarity relates the total cross section for neutrino-nucleon scattering to the neutrino-nucleon forward scattering amplitude. Assuming the validity of the perturbative expansion of the forward amplitude in the weak coupling constant, we derive a unitarity bound on the inelastic cross section. The inelastic cross section saturates this bound at a typical neutrino energy Eν ≃ 108 GeV. This impl...

Standard Model Higgs cross sections (NLO) and PYTHIA

Recent NLO results of the SM Higgs cross section at the LHC differ by factors of up to 2 from the LO cross section estimates currently used inside PYTHIA. We propose a scheme on how these NLO results can be used consistently inside the PYTHIA Monte Carlo simulations. Numerical results for Higgs are given for three recent parton distribution functions, MRS(R1), GRV(94)HO and CTEQ4M. For complete...

Resummation of Hadroproduction Cross-sections at High Energy

We reconsider the high energy resummation of photoproduction, electroproduction and hadroproduction cross-sections, in the light of recent progress in the resummation of perturbative parton evolution to NLO in logarithms of Q and x. We show in particular that the when the coupling runs the dramatic enhancements seen at fixed coupling, due to infrared singularities in the partonic cross-sections...