ESPOS Seminar: Three-dimensional simulations of oscillations in solar prominences

Los seminarios europeos en línea de física solar (ESPOS por sus siglas en inglés) son una serie de seminarios regulares celebrados por videoconferencia entre instituciones europeas. Se propone conectar grupos europeos de física solar a través de una serie regular de seminarios abiertos en línea. El objetivo es construir una plataforma efectiva y abierta para el intercambio de ideas científicas. Los seminarios en línea permiten a los investigadores compartir su trabajo de manera más amplia con una audiencia especializada, y dan exposición a la investigación de vanguardia para estudiantes y otros investigadores jóvenes que no viajan regularmente a conferencias.
Author: Andrés Adrover González
Title: Three-dimensional simulations in solar prominences
Date:  6 of February, 2020, at 11.00h
Place: Sala de Sminaris, 3er pis Dpt. Física, Edifici Mateu Orfila, UIB
Abstract:We numerically investigate the periodicity and damping of transverse and longitudinal oscillations in a 3D model of a curtain-shaped prominence. We carried out a set of numerical simulations of vertical, transverse and longitudinal oscillations with the high-order finite-difference Pencil Code. We solved the ideal magnetohydrodynamic (MHD) equations for a wide range of parameters, including the width and density of the prominence, and the magnetic field strength (B) of the solar corona. We studied the periodicity and attenuation of the induced oscillations. We found that longitudinal oscillations can be fit with the pendulum model, whose restoring force is the field aligned component of gravity, but other mechanisms such as pressure gradients may contribute to the movement. On the other hand, transverse oscillations are subject to magnetic forces. The analysis of the parametric survey shows, in agreement with observational studies, that the oscillation period (P) increases with the prominence width. For transverse oscillations we obtained that P increases with density and decreases with B. For longitudinal oscillations we also found that P increases with density, but there are no variations with B. The attenuation of transverse oscillations was investigated by analysing the velocity distribution and computing the Alfvén continuum modes. We conclude that resonant absorption is the mean cause. Damping of longitudinal oscillations is due to some kind of shear numerical viscosity.