Stellar activity as a tracer of moving groups

TL;DR

This study investigates stellar activity in the solar neighborhood, revealing that stars near known moving groups are generally more active, supporting their identification as young, kinematically bound stellar populations.

Contribution

The paper provides a comprehensive analysis linking stellar activity levels with moving group membership, supported by a new catalog and multi-data validation methods.

Findings

Stars near moving groups are more active than field stars.

Active stars are likely young and kinematically bound.

A catalog of stellar kinematics and activity levels is provided.

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 $\log R'_{\rm{HK}}$. 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.