5,063 research outputs found
Coherent pion production off nuclei at T2K and MiniBooNE energies revisited
As a result of a new improved fit to old bubble chamber data of the dominant
axial C_5^A nucleon-to-Delta form factor, and due to the relevance of this form
factor for neutrino induced coherent pion production, we re-evaluate our model
predictions in Phys. Rev. D79, 013002 (2009) for different observables of the
latter reaction. Central values for the total cross sections increase by 20% to
30%, while differential cross sections do not change their shape appreciably.
Furthermore, we also compute the uncertainties on total, differential and flux
averaged cross sections induced by the errors in the determination of C_5^A.
Our new results turn out to be compatible within about 1 sigma with the former
ones. Finally, we stress the existing tension between the recent experimental
determination of the sigma(CC coh \pi^+)/sigma(NC coh \pi^0) ratio by the
SciBooNE Collaboration and the theoretical predictions.Comment: 6 latex pages, 1 table, 2 figures. Shortened versio
Local Fermi gas in inclusive muon capture from nuclei
We compare local Fermi gas and shell model in muon capture in nuclei in order
to estimate the effect of finite nuclear size in low energy weak reactions.Comment: 6 pages, 8 figures. To be published in the Proceedings of 20th Max
Born Symposium, Wroclaw (Poland), December 7-10, 200
Helical buckling of a whirling conducting rod in a uniform magnetic field
We study the effect of a magnetic field on the behaviour of a conducting
elastic rod subject to a novel set of boundary conditions that, in the case of
a transversely isotropic rod, give rise to exact helical post-buckling
solutions. The equations used are the geometrically exact Kirchhoff equations
and both static (buckling) and dynamic (whirling) instability are considered.
Critical loads are obtained explicitly and are given by a surprisingly simple
formula. By solving the linearised equations about the (quasi-)stationary
solutions we also find secondary instabilities described by (Hamiltonian-)Hopf
bifurcations, the usual signature of incipient `breathing' modes. The boundary
conditions can also be used to generate and study helical solutions through
traditional non-magnetic buckling due to compression, twist or whirl.Comment: arXiv admin note: substantial text overlap with arXiv:0810.366
Nucleon Emision Off Nuclei Induced By Neutrino Interactions
We make a review of the main nuclear effects that affect neutrino-nucleus
cross sections. We discuss how the different models in the literature try to
describe these different effects, and thus try to compare between them. We
focus on the quasi-elastic reaction in the neutrino energy region of around 1
GeV, where recent data from MiniBoone are available. Among the issues discussed
are the different treatment of medium corrections to initial and nal state
nucleon wave functions and the problem of the rescattering of ejected nucleons.Comment: 5 pages, 5 figures. To appear in the proceedings for NuFact09; July
20-25, (2009) Illinois Institute of Technolog
A Rare Presentation of Invasive Tuberculosis of the Central Nervous System in an Immunocompetent Patient in a Nonendemic Country.
We herein report a rare case of a 25-year-old immunocompetent male patient with disseminated tuberculosis of central nervous system (CNS), first presenting as multiple cerebral lesions with no meningeal involvement. Subsequent diagnostic workup disclosed extensive peritoneal involvement. A broad differential diagnosis was considered, including neoplastic and infectious diseases. The diagnosis was confirmed with positive PCR result for Mycobacterium tuberculosis in the biopsied mesenteric tissue. The patient was started on tuberculostatic regimen with favorable outcome. No acquired or hereditary immunodeficiency was documented. Disseminated tuberculosis in immunocompetent individuals is extremely rare. Genetic susceptibility factors have been reported in individuals with extensive forms of the disease and a high index of suspicion is required, as observed in our case.info:eu-repo/semantics/publishedVersio
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