Astrophysikalisches Institut und
Universitäts-Sternwarte

Intro

The observations group at AIU concentrates on the direct imaging and spectroscopy of sub-stellar companions around young and nearby stars, in order to investigate the formation and early evolution of brown dwarfs and planets, in particular as companions of stars.

For this search, we use speckle and adaptive optics techniques at the 8m to 10m telescopes VLT,Subaru, Keck, and Gemini, as well as the Hubble Space Telescope. Most faint objects near bright stars are background objects, so that 2nd epoch follow-up imaging is neccessary for proper motion check and also optical and infrared follow-up spectroscopy of co-moving companion candidates. Previously, several young brown dwarfs were found in this program, e.g. the brown dwarf TWA-5 B and also GQ Lupi b, which may well be the first planet imaged directly.

This group also deals with many aspects related to old exo-planets, like innovative observations of exo-planet candidates previously found by radial velocity and searching for wide (sub-)stellar companions to the radial velocity exo-planet candidate host stars.

Members

• Ralph Neuhäuser: Science strategy, planet detection, GQ Lup and GQ Lup (on exoplanet.eu)

• Markus Mugrauer: Search for substellar companions and multiplicity of planet host stars

• Tobias Schmidt: young sub-stellar companions, spectroscopy, Cha, CrA, TWA, TucHorA

• Thomas Eisenbeiss: Archival analyses

• Tristan Roell: Astrometry

• Stefanie Rätz: Planet transit search

• Alexandra Költzsch: Variability of young stars

• Martin Vanko: Interferometric observations, planet transit search, and Darwin targets

• Christian Ginski: HST archive search for young companion

• Mohammad Moualla: Pleiades variability