Stellar activity as a tracer of moving groups

Abstract

We present the results of a study of the stellar activity in the solar neighborhood using complete kinematics (galactocentric velocities U, V, W) and the chromospheric activity index log R'(HK). We analyzed the average activity level near the centers of known moving groups using a sample of 2529 stars and found that the stars near these associations tend to be more active than field stars. This supports the hypothesis that these structures, or at least a significant part of them, are composed of kinematically bound, young stars. We confirmed our results by using GALaxy Evolution EXplorer (GALEX) UV data and kinematics taken from the Geneva-Copenhagen Survey for the stars in the sample. Finally, we present a compiled catalog with kinematics and activities for 2529 stars and a list of potential moving group members selected based on their stellar activity level.