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| Titel |
A parametric study of non-linear evolution of tearing mode with temperature anisotropy |
| VerfasserIn |
Iku Shinohara, Masaki Fujimoto |
| Konferenz |
EGU General Assembly 2013
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 15 (2013) |
| Datensatznummer |
250077696
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| Zusammenfassung |
| We have studied the non-linear evolution of the tearing instability with temperature
anisotropy, T-¥-T-- by using a 2-D full kinetic simulation. As predicted by the linear-theory,
e.g. Chen and Palmadesso (1984), Quest et al. (2010), the growth rate of the tearing mode
increases as higher anisotropy, T-¥-T--. Two parametric studies have been done:
(i) changing the current sheet thickness with the fixed anisotropy ratio, and (ii)
changing the anisotropy ratio and the ion-electron temperature ratio with a fixed
current sheet thickness. As a result, we found that event in a thick current sheet case,
D-λi = 4 (D is the current sheet thickness, and λi is the ion inertia length.), fast
growth emerges at the non-linear stage and the growth rate is almost proportional
to D-λi and that the growth rate and saturation level at the non-linear stage are
independent on parameters once the explosive growth starts. The most impressible results
are those (1) electron anisotropy plays important role to push the tearing mode
into the non-linear stage and (2) there exists a threshold value of the ion-electron
temperature ratio for enabling the explosive growth as the results of Tanaka et al.
(2004). We think that these facts may be a big hint to solve the triggering mechanism
of magnetic reconnection. We will show the results of our parametric study and
discuss possible physical meaning of the threshold value for the explosive evolution. |
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