Full-disk observations of the Sun to investigate flow structures in the chromosphere

• Applicant: Professor Dr. Hardi Peter
• Subject Area: Astrophysics and Astronomy
• Term: from 2008 to 2010
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 54780971

Cool stars like our Sun are surrounded by a million K hot corona. The chromosphere, named after the colorful appearance during solar eclipses, is the connection from the photosphere to the corona and can be considered as the root of the coronal structures. The chromosphere shows small structures on length scales below 1 Mm, e.g. bright points which are smaller than the convection pattern at solar surface, to prominences or coronal holes which can stretch over more than 100 Mm, i.e. a sizable fraction of the solar radius. Therefore observations combining a good spatial resolution with a very large field of view are needed for various chromospheric studies. The full-disk telescope ChroTel of the Kiepenheuer-Institut provides just such observations.The goal of the present project is to investigate the flow structures in the chromosphere, predominantly through the use of Doppler maps in the He I triplet at 1083 nm. Through this we will provide new information on the dynamic response of the chromosphere to photospheric driving, on large scale structures such as prominences and their disturbances as well as on the chromospheric source of the fast solar wind in coronal holes.

• DFG Programme: Research Grants