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| Titel |
Towards theoretical modeling of planet-induced stellar activity using A.I.K.E.F. simulations |
| VerfasserIn |
Jeremy Riousset, Uwe Motschmann, Ansgar Reiners, Christopher Marvin |
| Konferenz |
EGU General Assembly 2015
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 17 (2015) |
| Datensatznummer |
250114029
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| Publikation (Nr.) |
 EGU/EGU2015-14287.pdf |
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| Zusammenfassung |
| Plasma flows and turbulences in stellar atmospheres and chromospheres can be disturbed by
the presence of a planet in close orbit around the star. Such disturbances can be generated
through tidal interactions between the two, or through direct magnetic interaction between the
magnetic fields of the star and the planet. The presence of an outer disturber and its influence
on the generation of stellar activity, together with the knowledge about stars with no close
planets, provide a unique laboratory for the investigation of plasma turbulence in
stellar atmospheres. In this work we develop an integrated model covering the star
and the planet as an interacting system where gravitational and electromagnetic
forces are implemented self-consistently. The model is based on A.I.K.E.F. hybrid
code for simulating stellar wind interaction with astronomical bodies. Compared to
previous studies, the solar wind is no longer modeled as inflow/outflow boundary
conditions, but created instead by a second body representing a star inside the simulation
domain. The incorporation of the star is carried out based on Parker (1952) model for
slow rotating stars with moderate stellar magnetic fields or on the sophisticated
stellar wind model of Weber and Davis (1967) for fast rotators with strong stellar
magnetic fields. Such an approach is not without scaling constraints, which will be
discussed in this paper. Here, we present the first results for a configuration where the
planet is within the star’s Alfvén radius, i.e., where the stellar wind flow velocity is
subcritical. In this case, the resulting current system is extended and may even propagate
against the inflowing stellar wind with possible consequences for the stellar activity. |
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