MHD simulations of solar coronal structures: the interaction between a quiescent filament and a large-scale coronal wave

Data: 
25/11/2020 - 14:00 - 15:00
Local: 
Remoto, com transmissão pela internet

MHD simulations of solar coronal structures: the interaction between a quiescent filament and a large-scale coronal wave

Ernesto Zurbriggen

Universidade Mackenzie

Large-scale coronal waves can perturb distant quiescent filaments. After the occurrence of some flares, observations have reported oscillations in the dynamic and emission by faraway quiescent filaments. These kinds of oscillations are known as winking filaments; also, observations have pointed out that activation times of winking filaments coincide with the passage through them of a large-scale coronal wave-front. However often the perturber is not clearly detected. Even in some extreme cases these perturbations may give rise to an erupting filament. By MHD modelling we study whether winking filaments are compatible with perturbations exerted by a large-scale coronal wave, and whether reported oscillating Hα emissions due to Doppler effect may be a consequence of these perturbations. Carrying out ideal 2.5D MHD simulations we model the following scenario: a filament floating in the corona at quasi-equilibrium with its background; where the background environment is a gravitational stratified corona in hydrostatic equilibrium including the chromosphere and a thin transition region; and the perturbing coronal wave is modelled by a blast wave. In this talk we will present the result obtained. As a result of the interaction filaments exhibit a damping oscillatory movement. Dynamical-observable quantities such as amplitudes of oscillations, periods and damped time will be analysed. Furthermore, the oscillation of Hα emission owing to the Doppler effect as viewed from different line-of-sights will be presented.

 

Link da transmissão: https://www.youtube.com/c/AstronomiaIAGUSP/live