Astrophysics

Overview of the research activity

NASA Science Visualization Studio

The research activities of the Solar Physics Group are related with the Solar Atmosphere. In particular, the group performs research on the Seismology of coronal magnetic structures (loops, prominences, etc.); on the behaviour of solar activity (Asymmetries, periodicities, chaos, etc.), on MHD waves and instabilities in the solar corona and coronal rain dynamics.

Research lines:

1. Seismology of the Solar Corona: MHD seismology is a method of remote diagnostics of plasma structures combining observations of oscillatory motions with an interpretation in terms of MHD waves.

2. Behaviour of Solar Activity: Solar activity is produced by the emergence of magnetic flux through the photosphere forming active regions which include sunspots. Apart from sunspots, other manifestations of solar activity are solar flares, prominences, CME’s, etc. The behaviour of solar activity shows some particular features such as periodicities, asymmetries, lack of memory, etc which are worth to be investigated.

3. Waves and Instabilities in prominences: Prominence oscillations are commonly interpreted in terms of MHD waves, and this interpretation allows to perform prominence seismology. Furthermore, MHD instabilities are also observed in prominences and its interpretation would allow to understand the complex dynamics displayed by prominences

4. Coronal rain: Active region loops usually have temperatures of the order of 1 million K. But sometimes dense and cold (10.000 K) plasma blobs form high in these loops and start to fall under the action of the Sun’s gravity. The measured downward acceleration is considerably smaller than that of free-fall motion: at present we are interested in explaining this behaviour. In the future we plan to study other coronal rain features, e.g., its multi-thermal character or the conditions that lead to the formation of the cold condensations.

More information: http://solar.uib.es/