[Todos] CICLO DE COLOQUIOS CIENTIFICOS: Jueves 11 de Diciembre de 2014 a las 14:00 hs.

["Area Difusión IAFE"]

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                   CICLO DE COLOQUIOS CIENTÍFICOS
                  Instituto de Astronomía y Física del Espacio
                                CONICET-UBA
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 "Significance of heliospheric physics for the astrophysical problem of
cosmic ray anisotropies and numerical modeling thereof."

                     Barbara Lisbeth Krebl, Mag.
       Institute of Astro- and Particle Physics. University of Innsbruck
              Jueves 11 de Diciembre de 2014 a las 14:00 hs.
                       Aula del Edificio IAFE

The outer heliosphere represents the interface between the solar dominated
region of space and the interstellar medium. Its understanding is of
significance for both heliophysics and astrophysics. The Voyager
spacecraft are continuously improving the determination of the local
interstellar spectra of cosmic rays and the contribution of its anomalous
component that is accelerated in the region bounded by the solar wind
termination shock and the heliopause, i.e. the inner heliosheath. The IBEX
mission has increased our knowledge about the (local) interstellar
magnetic field, plasma and neutral gas surrounding the heliosphere and has
triggered a refined understanding of the effect of the outer heliosheath
(i.e. the region of the local interstellar medium (LISM) that is disturbed
by the presence of the heliosphere) on cosmic ray modulation. The
hypothesis that part of the observed cosmic ray anisotropy in the low-TeV
range is due to the structure of the heliosphere in connection with the
idea of a local acceleration due to magnetic reconnection has recently
gained new support from measurements made with the Matsushiro underground
muon detector, the Tibet Air Shower Array, the Super-Kamiokande and
MILAGRO. In order to allow for a quantitative analyses of the mentioned
observations, a model of the large-scale heliospheric structure and its
interstellar vicinity has to be implemented. While various such models
exist, the physics of the heliotail and the outer heliosheath have not
been addressed in sufficient detail. To achieve this, we are currently
implementing so-called logically rectangular grids in our numerical HD/MHD
framework, Cronos, which was developed by Ralf Kissmann. These are are
highly nonorthogonal grids, that have the advantages of being locally
adjustable to a problem’s geometry, avoiding coordinate singularities
as well as strongly differing cell sizes, and of allowing for the
straightforward implementation of adaptive mesh refinement.