Dynamics of Solar Convection

The Sun is the nearest star and thus enables us to observe ist fine structure in detail. A well known phenomenon is the solar granulation: hot material rises upwards, cools down and moves back again. This process is well established for relatively cool stars. The main motivation for this research project is to study the dynamical evolution of convective motions in detail. This will be achieved by a. high resolution white light, IR observations with the SVST in La Palma, high resolution observations with the VTT using the spectroscope. b. Theoretical modelling of the data, calculation of line profiles, derivation of line parameters, compare observations with theory. Since the convective overshoot layer is a boundary condition for solar models and the problem of higher atmospheric heating in the sun we hope to get a better insight into the understanding of the solar interior structure and the outer atmosphere These phenomena are related to the overall problem of solar activity cycles and since now the solar activity is rising again from minimum towards a maximum a detailed study is of great importance. In the research project we want to concentrate on the question of distribution of convective elements with size, decay to turbulence, regions of turbulence occurence, connection between granulation and mesogranulation, occurence of energy dissipation and hypersonic motions. Since a typical observing run will yield some Gbytes of data material and the implementation of the computer codes and development of new programs requires a lot of time, one PhD student is needed to colloborate for three years.