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Titel |
Reconnection in the initiation phase of Coronal Mass Ejections |
VerfasserIn |
Alexander Soenen, Carla Jacobs, Stefaan Poedts, Alessandro Bemporad, Malgorzata Selwa, Clare Parnell |
Konferenz |
EGU General Assembly 2010
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Medientyp |
Artikel
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Sprache |
Englisch
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Digitales Dokument |
PDF |
Erschienen |
In: GRA - Volume 12 (2010) |
Datensatznummer |
250044437
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Zusammenfassung |
We present the first results of a comparison between ideal and
resistive magnetohydrodynamic (MHD) simulations of coronal mass
ejection (CME) onset and early evolution performed using the
Versatile Advection Code (VAC). We consider a 2.5D
(axi-symmetric) setup with a quadrupolar magnetic field (triple
arcade structure) superposed on a solar wind model and focus on
the different magnetic reconnection events that occur when this
configuration is triggered to yield a breakout CME. Clearly, in
the ideal MHD, the magnetic reconnection is only due to
numerical dissipation and thus only mimicking this fundamental
physical process. In the resistive MHD simulations, however,
the magnetic resistivity is taken to be larger than the
numerical dissipation so that 'physical' reconnection occurs,
although the electrical conductivity in the model is much lower
than in the solar corona. We perform a parameter study with
different constant resistivity values to examine how this
affects the CME initiation phase and in particular the
different magnetic reconnection events associated with CME
initiation. We also consider an anomalous resistivity model to
introduce a more realistic model for locally enhanced
current-driven anomalous resistivity. We try to determine the
magnetic reconnection rates in the simulated events and compare
these with the values computed from detailed observations. |
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