Searching for Stellar Associations in Gaia DR2

Brolan Jennings, Jeff Andrews, Marcel Agüeros, Julio Chanamé, Ethan Deneault, Simon Schuler
2021
We present preliminary results of a search for previously unidentifed stellar associations in the second data release (DR2) from the European Space Agency's Gaia satellite. Gaia DR2 contains precise astrometric data on more than 1.2 billion stars in the Milky Way Galaxy. We have modifed a Python code originally intended to identify wide stellar binaries through a Bayesian formulation, which includes correlated uncertainties in the proper motions and parallaxes, to expand it to larger stellar
more » ... ups of 10 or more stars. The search volume includes the whole sky within 500 parsecs of the sun, where stellar parallaxes are more discernible. The code has been optimized to flter out background stars by testing over several well known stellar associations, including the Pleiades open cluster and the Scorpius-Centaurus Association. We have been able to successfully identify the Pleiades, Upper Scorpius Centaurus, and Messier 39 stellar associations with our code and are now searching the sky for previously unidentifed associations. Identifying new stellar associations will help constrain models of the dynamical evolution of the Galaxy.
doi:10.48497/vdar-nn31 fatcat:rxbggi5mlnhfjnrir4ld54qmqm