Conveners
Poster Session 2.3
- Georgia Tsiropoula (National Observatory of Athens)
We have carried out the first comprehensive investigation of enhanced line emission from molecular hydrogen, H$_{2}$ at 1333.79 Å, observed at flare ribbons in SOL2014-04-18T13:03. The cool H$_{2}$ emission is known to be fluorescently excited by Si IV 1402.77 Å UV radiation and provides a unique view of the temperature minimum region (TMR). Strong H$_{2}$ emission was observed when the Si IV...
The Evershed flow is one of the most outstanding features observed in sunspot penumbrae. It is a plasma flow running along penumbral filaments radially outwards and towards the moat of sunspots. This flow was first observed more than a century ago. Nevertheless, in the past decade, observations have shown unusual counter Evershed flows (CEFs) that run in the opposite direction, towards the...
The solar corona is characterised by its puzzling multi-million degree component. On the other hand, observations in the last decade have shown that the corona also contains a large amount of coronal rain, 10-100 times cooler and denser than the surroundings. The properties of coronal rain are now known to be strongly linked to the coronal heating properties, but its origin, dynamics, and...
We discuss the diagnostics of plasma jets in the solar corona from multiwavelength imaging observations in the microwave band. We present several events observed with RATAN-600, Siberian Radioheliograph, and Nobeyama Radioheliograph. Obtained data provide us with spatially resolved imaging information alongside microwave flux observations at several frequencies. To analyze the context...
High resolution observations have shown the ubiquity of Alfvénic waves in the solar atmosphere. Recently, torsional Alfvén waves in coronal flux tubes have been first detected. Here, we perform numerical simulations of torsional Alfvén waves and study their nonlinear evolution. We consider a cylindrical, radially inhomogeneous, and straight coronal magnetic flux tube that is line-tied at two...
It has been stated for a long time that the solar atmospheric plasma is not in a neutral state nor in a fully ionized state. The solar plasma is composed of different species, and it can be considered that each of them behaves like a fluid interacting with the rest of the species via collisions. When the collisional coupling is strong, the plasma mostly behaves as a single fluid. If this...
The Fe I 6301.5 Å and 6302.5 Å lines are widely used to probe the solar photosphere. They are known to be affected by the non-local thermodynamic equilibrium (NLTE) conditions due to the ultraviolet overionisation of iron atoms in the solar atmosphere. This leads to deviations in their level populations based on Saha-Boltzmann statistics. When inverting their Stokes profiles to determine...
