Multiple kinematical populations in Vela OB2 from Gaia DR1 data

Abstract

Recent results using radial-velocity measurements from the Gaia-ESO Survey have led to the discovery of multiple kinematic populations across the Vela OB2 association. We present here a proper-motion study of the same region. Our aim is to test whether the radial-velocity populations have a counterpart in proper-motion space, and if so, how the two sets of kinematical data complement each other. This work is based on parallaxes and proper motions from the TGAS catalog, as part of Gaia DR1. Two distinct proper-motion populations are found dispersed across ~5 degrees (or ~30 pc at their likely distances). Their detailed correspondence to the radial-velocity populations could not be tested, because of the paucity of common objects. However, compelling indications are found that one of the new proper-motion populations consists mostly of members of the young cluster NGC 2547, and the other is related to the gamma Vel cluster. Constraints on the age of the two populations, both of which appear to be only 10-35 Myr old, and their possible mutual interactions within the last 1.5 Myrs, are discussed.

arXiv comment4 pages, 6 figures, accepted for publication on A&A Letters

References in corpus (12)

• The Gaia mission
• Gaia Data Release 1. Summary of the astrometric, photometric, and survey properties
• A Hipparcos census of the nearby OB associations
• Gaia Data Release 1: Astrometry - one billion positions, two million proper motions and parallaxes
• Gaia broad band photometry
• The stellar association around Gamma Velorum and its relationship with Vela OB2
• A maximum likelihood method for fitting colour-magnitude diagrams
• The Gaia-ESO Survey: Kinematic structure in the Gamma Velorum Cluster
• The Lithium Depletion Boundary in NGC 2547 as a test of pre-main-sequence evolutionary models
• The Gaia-ESO Survey: Lithium depletion in the Gamma Velorum cluster and inflated radii in low-mass pre-main-sequence stars
• The discovery of a low mass, pre-main-sequence stellar association around gamma Velorum
• The Gaia-ESO Survey: Discovery of a spatially extended low-mass population in the Vela OB2 association

Cited by in corpus (15)

• 3D mapping of young stars in the solar neighbourhood with Gaia DR2
• Stars with Photometrically Young Gaia Luminosities Around the Solar System (SPYGLASS) I: Mapping Young Stellar Structures and their Star Formation Histories
• Expanding associations in the Vela-Puppis region: 3D structure and kinematics of the young population
• The stellar population of Sco OB2 revealed by Gaia DR2 data
• A ring in a shell: the large-scale 6D structure of the Vela OB2 complex
• A sextet of clusters in the Vela OB2 region revealed by Gaia
• The Gaia DR2 view of the Gamma Velorum cluster: resolving the 6D structure
• Unveiling the star formation history of the Upper Scorpius association through its kinematics
• Disruption of Hierarchical Clustering in the Vela OB2 Complex and the Cluster Pair Collinder 135 and UBC7 with Gaia EDR3: Evidence of Supernova Quenching
• Discovery of a young stellar "snake" with two dissolving cores in the solar neighborhood
• A tale of two clusters: dynamical history determines disc survival in Tr14 and Tr16 in the Carina Nebula
• The dynamics of the γ Vel cluster and nearby Vela OB2 association
• The low mass population of the Vela OB2 association from Gaia
• The Structure and 3D Kinematics of Vela OB2
• Open superclusters I: The most populated primordial groups of open clusters in the third quadrant of the Galactic disc