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Numerical simulation of the internal plasma dynamics of post-flare loops
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andrea costa Submitted: 2009-10-02 17:20
We integrate the MHD ideal equations of a slender flux tube to simulate the internal
plasma dynamics of coronal post-flare loops. We study the onset and evolution of the internal
plasma instability to compare with observations and to gain insight into physical processes and
characteristic parameters associated with flaring events. The numerical approach uses a finite-
1
volume Harten-Yee TVD scheme to integrate the 1D 2 MHD equations specially designed to
capture supersonic flow discontinuities. We could reproduce the observational sliding down
and upwardly propagating of brightening features along magnetic threads of an event occurred
on October 1st, 2001. We show that high?speed downflow perturbations, usually interpreted
as slow magnetoacoustic waves, could be better interpreted as slow magnetoacoustic shock
waves. This result was obtained considering adiabaticity in the energy balance equation. How-
ever, a time?dependent forcing from the basis is needed to reproduce the reiteration of the
event which resembles observational patterns -commonly known as quasi?periodic pulsations
(QPPs)- which are related with large scale characteristic longitudes of coherence. This result
reinforces the interpretation that the QPPs are a response to the pulsational flaring activity.
Authors: Fernández, Carlos, Costa, Andrea, Elaskar, Sergio, Schulz, Walkiria
Projects: TRACE
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Publication Status: Accepted MNRAS
Last Modified: 2009-10-05 09:41
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