Astrophysical Spectropolarimetry

Astrophysical Spectro-polarimetry is an already well established research project that was started at the Institute of Astronomy at ETH Zurich, and has been continued and further developed at Istituto Ricerche Solari Locarno (IRSOL) in collaboration with SUPSI, the University of Applied Sciences and Arts of Southern Switzerland. The main aim of the project is the measurement and theoretical interpretation of weak polarization signatures observed in the Sun's spectrum. This allows the application of the Hanle effect to measure spatially unresolved tangled magnetic fields, which represent a main component of solar magnetism. Besides the observations that can be performed at IRSOL, new observations with larger telescopes allowing better spatial resolution are needed. We are therefore installing a ZIMPOL-3 system at the new German GREGOR telescope on Tenerife. The objective is to complement and extend the observations done at IRSOL with the greatly improved angular resolution that will be possible with GREGOR. In addition we will pursue a project that links our solar programs at IRSOL with stellar physics: With Observatoire de Genève we will explore planet engulfing scenarios in extra-solar systems with the help of an SNF-funded PhD position.