Pulse-beam heating of deep atmospheric layers triggering their oscillations and upwards moving shocks that can modulate the reconnection in solar flares

Autor: Jelínek, P., Karlický, M.
Rok vydání: 2019
Předmět:
Zdroj: A&A 625, A3 (2019)
Druh dokumentu: Working Paper
DOI: 10.1051/0004-6361/201935188
Popis: We study processes occurring after a sudden heating of the chromosphere at the flare arcade footpoints which is assumed to be caused by particle beams. For the numerical simulations we adopt a 2-D magnetohydrodynamic (MHD) model, in which we solve a full set of the time-dependent MHD equations by means of the FLASH code, using the Adaptive Mesh Refinement (AMR) method. In the initial state we consider a model of the solar atmosphere with densities according to the VAL-C model and the magnetic field arcade having the X-point structure above, where the magnetic reconnection is assumed. We found that the sudden pulse-beam heating of the chromosphere at the flare arcade footpoints generates magnetohydrodynamic shocks, one propagating upwards and the second one propagating downwards in the solar atmosphere. The downward moving shock is reflected at deep and dense atmospheric layers and triggers oscillations of these layers. These oscillations generate the upwards moving magnetohydrodynamic waves that can influence the above located magnetic reconnection in a quasi-periodic way. Because these processes require a sudden heating in very localized regions in the chromosphere therefore they can be also associated with seismic waves.
Databáze: arXiv