Conveners
Poster Session 4.2
- Jasmina Magdalenic (Solar-Terrestrial Centre of Excellence—SIDC, Royal Observatory of Belgium)
Why the atmosphere of the Sun is orders of magnitudes hotter than its surface is a long standing question in Solar Physics. Over the years, many studies have looked at the potential role of MHD waves in sustaining these high temperatures. In this study, we use 3D MHD simulations to investigate (driven) Alfvenic waves in a coronal loop. Due to the radial density profile, resonant absorption (or...
Recent observational and theoretical studies indicate that the damping of solar coronal loop oscillations depends on the oscillation amplitude. We consider the mechanisms of linear resonant absorption and of nonlinear damping due to the development of the Kelvin-Helmholtz instability. We confront theoretical predictions from these models with observed data in the plane of observables defined...
High-resolution solar observations from both space-borne and ground-based telescopes have revealed ubiquitous photospheric vortical motions in quiet, as well as in active regions. In observations of the chromosphere, obtained in spectral lines, such as the Hα and the Ca II IR, they appear as spiral-shaped or circular dark patches. These so called “chromospheric swirls” are considered to be of...
ALMA millimeter wavelength images of the Sun show significant correspondence with the solar magnetograms. We analyze the observed correspondence by comparing ALMA solar images taken at 1.2 and 3.0 mm with SDO/HMI line-of-sight magnetograms. We find that the active regions and the chromospheric network show a positive correlation where the brightness temperature increases with the...
We revisit the so-called levitation-condensation mechanism for the \textit{ab-inito} formation of solar prominences: cool and dense clouds in the million-degree solar atmosphere. A flux rope is formed in response to the deformation of a force-free coronal arcade by controlled magnetic footpoint motions and subsequent reconnection. Existing coronal plasma gets lifted within the forming rope,...
The solar atmosphere is hotter than predicted by assuming radiative equilibrium. This is most obviously evidenced by the high temperature of the solar corona, but the bulk of the energy deposition happens already down in the much cooler chromosphere. While in recent years we have gain detailed understanding of many important processes that must be at work in the chromosphere, also from...
Network jets at transition region temperatures of ca. 0.1 MK have been observed to be widespread enough to provide substantial mass and energy to the upper solar atmosphere. Previous studies of this phenomena have mostly focused on near-limb and broadband imagery data and ascribed propagating intensity disturbances as mass motions. Thus, the nature of plasma flows in these jets and their...
