Studies of Higher Twist and Higher Order Effects in NLO and NNLO QCD Analysis of Lepton-Nucleon Scattering Data on F_2 and R =sigma_L/sigma_T

We report on the extraction of the higher twist contributions to F_2 and R = sigma_L/sigma_T from the global NLO and NNLO QCD fits to lepton nucleon scattering data over a wide range of Q^2. The NLO fits require both target mass and higher twist contributions at low Q^2. However, in the NNLO analysis, the data are described by the NNLO QCD predictions (with target mass corrections) without the need for any significant contributions from higher twist effects. An estimate of the difference between NLO and NNLO parton distribution functions is obtained.Comment: 5 pages, 6 figures, submitted to Eur. Phys.

Modeling Neutrino and Electron Scattering Cross Sections in the Few GeV Region with Effective LOPDFsLO PDFs

We use new scaling variables $x_w$ and $\xi_w$, and add low $Q^2$ modifications to GRV94 and GRV98 leading order parton distribution functions such that they can be used to model electron, muon and neutrino inelastic scattering cross sections (and also photoproduction) at both very low and high energie.Comment: 8 pages, 3 figures, Invited talk given by Arie Bodek at the X Mexican School of Particles and Fields, Playa del Carmen, Mexico, 200

Extraction of Neutrino Flux with the Low ν\nu Method at MiniBooNE Energies

We describe the application of the `low-$\nu$' method to the extraction of the neutrino flux at MiniBooNE energies. As an example, we extract the relative energy dependence of the flux from published MiniBooNE quasielastic scattering cross sections with $\nu < 0.2$ GeV and $\nu < 0.1$ GeV (here $\nu$ is the energy transfer to the target). We find that the flux extracted from the `low-$\nu$' cross sections is consistent with the nominal flux used by MiniBooNE. We fit the MiniBooNE cross sections over the entire kinematic range to various parametrizations of the axial form factor. We find that if the overall normalization of the fit is allowed to float within the normalization errors, the extracted values of the axial vector mass are independent of the flux. Within the Fermi gas model, the $Q^2$ distribution of the MiniBooNE data is described by a standard dipole form factor with $M_A=1.41\pm0.04$ GeV. If nuclear transverse enhancement in the vector form factors is accounted for, the data are best fit with a modified dipole form factor with $M_A=1.10\pm 0.03$ GeV.Comment: 5 pages, 6 figures, (presented by A. Bodek at CIPANP 2012, St. Petersburg, FL, June 2012, and at NuFact 2012, Williamsburg, VA, July 2012

Ambiguities of neutrino(antineutrino) scattering on the nucleon due to the uncertainties of relevant strangeness form factors

Strange quark contributions to neutrino(antineutrino) scattering are investigated on the nucleon level in the quasi-elastic region. The incident energy range between 500 MeV and 1.0 GeV is used for the scattering. All of the physical observable by the scattering are investigated within available experimental and theoretical results for the strangeness form factors of the nucleon. In specific, a newly combined data of parity violating electron scattering and neutrino scattering is exploited. Feasible quantities to be explored for the strangeness contents are discussed for the application to neutrino-nucleus scattering.Comment: 17 pages, 7 figures, submit to J. Phys.

Higher Twist, ξw\xi_w Scaling, and Effective LOPDFsLO PDFs for Lepton Scattering in the Few GeV Region

We use a new scaling variable $\xi_w$, and add low $Q^2$ modifications to GRV98 leading order parton distribution functions such that they can be used to model electron, muon and neutrino inelastic scattering cross sections (and also photoproduction) at both very low and high energies.Comment: 6 pages, 3 figures. To be published in J. Phys. G (Conf. Proceedings) based on two talks by Arie Bodek at the NuFact$'02$ conference, Imperial College, London, England, July 200

Polarization effects in tau production by neutrino

We studied polarization effects in tau production by neutrino-nucleon scattering. Quasi-elastic scattering, $Delta$ resonance production and deep inelastic scattering processes are taken into account for the CERN-to-Gran Sasso projects. We show that the tau produced by neutrino has high degree of polarization, and its spin direction depends non-trivially on the energy and the scattering angle of tau in the laboratory frame.Comment: 6 pages, 5 eps figures, espcrc2.sty; Proceedings of the 3rd International Workshop on Neutrino-Nucleus Interactions in the Few GeV Region (NuInt04), March 17-21, 2004, Gran Sasso, Italy; minor changes, typos in Eq. (6) correcte