151 research outputs found
Final-State Interactions in the Superscaling Analysis of Neutral-Current Quasielastic Neutrino Scattering
Effects of strong final-state interactions in the superscaling properties of
neutral-current quasielastic neutrino cross sections are investigated using the
Relativistic Impulse Approximation as guidance. First- and second-kind scaling
are analyzed for neutrino beam energies ranging from 1 to 2 GeV for the cases
of 12C, 16O and 40Ca. Different detection angles of the outgoing nucleon are
considered in order to sample various nucleon energy regimes. Scaling of the
second kind is shown to be very robust. Validity of first-kind scaling is found
to be linked to the kinematics of the process. Superscaling still prevails even
in the presence of very strong final-state interactions, provided that some
kinematical restrains are kept, and the conditions under which superscaling can
be applied to predict neutral-current quasielastic neutrino scattering are
determined.Comment: 39 pages, 16 figures, accepted for publication in Phys. Rev.
Relativistic descriptions of quasielastic charged-current neutrino-nucleus scattering: application to scaling and superscaling ideas
The analysis of the recent experimental data on charged-current
neutrino-nucleus scattering cross sections measured at MiniBooNE requires fully
relativistic theoretical descriptions also accounting for the role of final
state interactions. In this work we evaluate inclusive quasielastic
differential neutrino cross sections within the framework of the relativistic
impulse approximation. Results based on the relativistic mean field potential
are compared with the ones corresponding to the relativistic Green function
approach. An analysis of scaling and superscaling properties provided by both
models is also presented.Comment: 11 pages, 8 figures, version accepted for publication in Physical
Review
Relativistic descriptions of final-state interactions in charged-current quasielastic neutrino-nucleus scattering at MiniBooNE kinematics
The results of two relativistic models with different descriptions of the
final-state interactions are compared with the MiniBooNE data of
charged-current quasielastic cross sections. The relativistic mean field model
uses the same potential for the bound and ejected nucleon wave functions. In
the relativistic Green's function (RGF) model the final-state interactions are
described in the inclusive scattering consistently with the exclusive
scattering using the same complex optical potential. The RGF results describe
the experimental data for total cross-sections without the need to modify the
nucleon axial mass.Comment: 5 pages 3 figure
Relativistic Models for Quasi-Elastic Neutrino-Nucleus Scattering
Two relativistic approaches to charged-current quasielastic neutrino-nucleus
scattering are illustrated and compared: one is phenomenological and based on
the superscaling behavior of electron scattering data and the other relies on
the microscopic description of nuclear dynamics in relativistic mean field
theory. The role of meson exchange currents in the two-particle two-hole sector
is explored. The predictions of the models for differential and total cross
sections are presented and compared with the MiniBooNE data.Comment: 3 pages, 3 figures, Proceedings of PANIC 2011, MIT, Cambridge, MA,
July 201
Final-state interactions and superscaling in the semi-relativistic approach to quasielastic electron and neutrino scattering
The semi-relativistic approach to electron and neutrino quasielastic
scattering from nuclei is extended to include final-state interactions.
Starting with the usual non-relativistic continuum shell model, the problem is
relativized by using the semi-relativistic expansion of the current in powers
of the initial nucleon momentum and relativistic kinematics. Two different
approaches are considered for the final-state interactions: the Smith-Wambach
2p-2h damping model and the Dirac-equation-based potential extracted from a
relativistic mean-field plus the Darwin factor. Using the latter the scaling
properties of and cross sections for intermediate
momentum transfers are investigated.Comment: 36 pages, 17 figure
AB responses: from bare nucleons to complex nuclei
We study the occurrence of factorization in polarized and unpolarized
observables in coincidence quasi-elastic electron scattering. Starting with the
relativistic distorted wave impulse approximation, we reformulate the effective
momentum approximation and show that the latter leads to observables which
factorize under some specific conditions. Within this framework, the role
played by final state interactions and, in particular, by the spin-orbit term
is explored. Connection with the nonrelativistic formalism is studied in depth.
Numerical results are presented to illustrate the analytical derivations and to
quantify the differences between factorized and unfactorized approaches.Comment: 26 pages, 5 figures. Improved and extended version. To be published
in Phys. Rev.
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