291 research outputs found
Two-pion decay modes of the N*(1440) in n p -> d pi pi
A simple model for the n p -> d pi pi reaction has been developed. It is
shown that the deuteron momentum spectra measured at T_n = 795 MeV can be
understood in terms of the Roper excitation and its N pi pi decay modes. A
similar pattern, recently observed in p p -> p p pi+ pi-, can be explained in
the same way.Comment: 3 pages, 5 figures. Presented at 16th International Conference on
Few-Body Problems in Physics, Taipei, Taiwan, 6-10 March 200
Theoretical highlights of neutrino-nucleus interactions
The recent theoretical developments in the field of neutrino-nucleus
interactions in the few-GeV region are reviewed based on the presentations made
at the NuInt09 Workshop. The topics of electron scattering and its connections
with neutrino interactions, neutrino induced quasielastic scattering and pion
production (coherent and incoherent) are covered, with special emphasis on the
challenges that arise in the comparison with new experimental data.Comment: Plenary talk at NuFact09, Chicago, July 20-25, 200
Charged current weak production of the Delta resonance
The charge changing weak production of Delta in nucleons and nuclei is
studied. The reactions e^{-} p -> Delta^{0} \nu_{e} and e^{+} p -> Delta^{++}
\bar{\nu}_{e} are considered as a possible source of information about the weak
N-Delta transition form factors. The low q^2 BNL data on neutrino production of
Delta are used to extract the axial vector N-Delta coupling, taking into
account the deuteron structure and the Delta width. Finally, pion production
induced by neutrinos in ^{16}O in the Delta region, relevant to atmospheric
neutrino experiments, is investigated.Comment: 4 pages, 2 figures. To appear in Proceedings of PANIC9
Quasielastic Scattering at MiniBooNE Energies
We present our description of neutrino induced charged current quasielastic
scattering (CCQE) in nuclei at energies relevant for the MiniBooNE experiment.
In our framework, the nucleons, with initial momentum distributions according
to the Local Fermi Gas model, move in a density- and momentum-dependent mean
field potential. The broadening of the outgoing nucleons due to nucleon-nucleon
interactions is taken into account by spectral functions. Long range (RPA)
correlations renormalizing the electroweak strength in the medium are also
incorporated. The background from resonance excitation events that do not lead
to pions in the final state is also predicted by propagating the outgoing
hadrons with the Giessen semiclassical BUU model in coupled channels (GiBUU).
We achieve a good description of the shape of the CCQE Q2 distribution
extracted from data by MiniBooNE, thanks to the inclusion of RPA correlations,
but underestimate the integrated cross section when the standard value of MA =
1 GeV is used. Possible reasons for this mismatch are discussed.Comment: 6 pages, 4 figures, Proceedings of the Sixth International Workshop
on Neutrino-Nucleus Interactions in the Few-GeV Region (NuInt09), May 18-22,
Sitges, Barcelona, Spai
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