Research Dark Energy Team Thomas Reiprich We study cosmology, galaxy clusters, and supermassive black holes over a range of wavelengths including X-ray, optical, and radio data. more ... Radio Astronomy & Interstellar Medium Prof. Frank Bigiel Our group focuses on observational studies of the distribution and the physical properties of gas and dust and their role in the star formation process in galaxies. more ... Gravitational Lensing and Cosmology Peter Schneider Gravitational Lensing and Cosmology; Theory and observations of weak and cluster lensing, Dark matter and Dark Energy more ... Millimeter/sub-millimeter astronomy Frank Bertoldi Star formation, galaxy evolution, ISM in galaxies, observational cosmology more ... Radio- and X-ray astronomy Juergen Kerp The scientific interest of the group is focused onto two very different wavelength regimes. However, the combined analysis offers a wealth of information about the physical conditions of the objects of interest, ranging from the Milky Way to active galact more ... The large-scale structure of the Universe Cristiano Porciani Cosmology, Galaxy Clustering, Dark Matter and Dark Energy, Physics of the Intergalactic Medium, Structure of Dark-Matter Halos and Galaxy Formation. more ... Stellar Astrophysics Norbert Langer Research topics include the evolution of single and binary stars, nucleosynthesis, supernovae and gamma-ray bursts, and stellar and circumstellar hydrodynamics. more ...