Astronomy seminar - High-contrast imaging of low-mass companions

The search for exoplanets, i.e., planets orbiting other stars than the Sun, is a relatively new research field, but has already established itself as one of the most prolific and intriguing areas of astronomy. By now we are in a situation where the focus is not only on finding companions to stars, but also on characterising their atmospheres and physical properties, which overall allows us to put our Solar System into context. In this seminar I will provide an introduction to the basis of the direct imaging technique, and discuss how it can be used to find and characterise low-mass companions. In particular, I will present the first direct imaging survey aimed at discovering circumbinary planets (SPOTS: Search for Planets Orbiting Two Stars), which includes the observations of 62 targets with VLT/NaCo and VLT/SPHERE, and a statistical analysis on the findings. These results put constraints on the population of giant planets and brown dwarfs on wide orbits. Moreover, I will present a second project where the new SCExAO/CHARIS integral field spectrograph is used to constrain the physical properties of a young stellar triple system via low-resolution spectroscopy. The observational data seem to point to a model age-mass discrepancy for young systems.