A Gaia View on the Star Formation in the Monoceros OB1 and R1 Associations

Abstract Stellar kinematics provides the key to understanding star formation process. In this respect, we present a kinematic study of Monoceros OB1 (Mon OB1) and R1 R1) associations using recent Gaia data radial velocities stars derived from high-resolution spectroscopy literature. A total 728 members are selected criteria based on intrinsic properties young stars, parallaxes, proper motions. The spatial distribution show that these have distinct substructures. Mon OB1, find one northern group two southern groups. is composed three small stellar groups spatially kinematically distinct. Some found in halo around associations. We detect patterns expansion for most addition, signature rotation, which an important constraint cluster formation. history slightly revised. Star first occurred region subsequently region. Recent star-forming events ignited deeper into region, while some escaping forming halo. might formed at same epoch as OB1. Given taking place different scales along large arc-like structure, may be results hierarchical