https://doi.org/10.1140/epjd/e2009-00124-7
Computational study of impulsively generated standing slow acoustic waves in a solar coronal loop
1
University of South Bohemia, Faculty of Science, Branišovská 31, 370 05 České Budějovice, Czech Republic
2
Astronomical Institute, Academy of
Sciences of the Czech Republic, v. v. i., Fričova
258, 251 65 Ondřejov, Czech Republic
Corresponding author: a pj@matfyz.cz
Received:
3
September
2008
Revised:
7
January
2009
Published online:
28
April
2009
We numerically investigated standing slow acoustic waves impulsively excited in a solar coronal loop by gas pressure and mass density perturbations in one-dimensional space. The corresponding computer model is described by the hydrodynamic equations that are solved numerically by means of the so-called flux limiters methods on uniformly structured mesh. We discuss the fundamental mode and the first harmonic mode which are generated in dependence on position of the initial perturbation in the numerical box. We show how the standing slow acoustic waves are generated in the corona, where they are trapped in space between two dense layers as in the resonator, and how their energy leaks from the corona to the dense layers. We found that this leakage increases with the decrease of the density jump at the transition region. We also studied the case when the perturbation is initiated at the transition region. We found that even in this case the standing wave is formed, but their energetics is influenced by the evaporation of the plasma from the transition region into the corona.
PACS: 95.30.Lz – Hydrodynamics / 94.20.wf – Plasma waves and instabilities / 96.60.pf – Coronal loops, streamers / 52.65.-y – Plasma simulation
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2009