Searching for planets in the dustiest debris disk systems with high contrast imaging
Abstract
Debris dust is the second-generation collisional debris generated around stars greater than a few Myr. For debris dust to be observed, it must be constantly regenerated by planetesimal collisions, since the dust is quickly removed from systems by stellar winds or the Poynting-Robertson effect. Dust is therefore believed to be a signpost for massive, long-period planets, whose gravitational influence perturbs the orbit of planetesimals in the system, and causes them to collide. We have been searching for planets and brown dwarfs around some of the dustiest stars detected with WISE, using the SPHERE high contrast imager at the VLT. Many of our targets have dust quanitities similar to, or greater than, the famous HR8799 system. Although no planets are observed we detect three new stellar companions, two of which are mid-M type objects. We infer that these companions are likely to be responsible for exciting the planetesimal belt and elevating the levels of debris dust in these systems. Intriguingly, two of these stellar companions appear to have evolved star hosts. This is highly unusual, since on the general trend is for older stars to host fainter disks. In this talk I will present the results of this survey, and comment on the many ways that debris disks can help us to understand exoplanet populations more broadly.
- Publication:
-
American Astronomical Society Meeting Abstracts #235
- Pub Date:
- January 2020
- Bibcode:
- 2020AAS...23525402M