6,458 research outputs found
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
We use new scaling variables and , and add low
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 Method at MiniBooNE Energies
We describe the application of the `low-' 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 GeV and GeV (here is the
energy transfer to the target). We find that the flux extracted from the
`low-' 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 distribution of the MiniBooNE data
is described by a standard dipole form factor with 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
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, Scaling, and Effective for Lepton Scattering in the Few GeV Region
We use a new scaling variable , and add low 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 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, 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
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