The low mass population of the Vela OB2 association from Gaia

Abstract

The first Gaia Data Release presents an opportunity to characterise the low-mass population of OB associations, providing larger statistical samples and better constraints on the formation and evolution of clusters and associations. Using previously known low mass members in a small region of Vela OB2 we have designed selection criteria that combine Gaia and 2MASS photometry, independently of any astrometric information, to identify low-mass pre-main-sequence (PMS) stars over the wider association area. Our method picks out the known clusters of young stars around ${\gamma }^2$ Velorum and NGC-2547, but also identifies other over-densities that may represent previously unknown clusters. There are clear differences in the spatial distributions of the low-mass and the high-mass OB populations, suggesting either that the structure and dynamics of these populations has evolved separately or that the initial mass function can vary considerably on small scales within a single association.

arXiv comment6 pages, 4 figures, accepted for publication in MNRAS

References in corpus (27)

• Astropy: A Community Python Package for Astronomy
• The Gaia mission
• Embedded Clusters in Molecular Clouds
• Intrinsic Colors, Temperatures, and Bolometric Corrections of Pre-Main Sequence Stars
• Gaia Data Release 1. Summary of the astrometric, photometric, and survey properties
• Grids of stellar models with rotation - I. Models from 0.8 to 120 Msun at solar metallicity (Z = 0.014)
• New evolutionary models for pre-main sequence and main sequence low-mass stars down to the hydrogen-burning limit
• A Hipparcos census of the nearby OB associations
• Gaia broad band photometry
• On the fraction of star formation occurring in bound stellar clusters
• The stellar association around Gamma Velorum and its relationship with Vela OB2
• A Spitzer view of protoplanetary disks in the gamma Velorum cluster
• The relation between the most-massive star and its parental star cluster mass
• XHIP: An Extended Hipparcos Compilation
• The Kinematics of the Scorpius-Centaurus OB Association from Gaia DR1
• On the function describing the stellar initial mass function
• 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
• γ^2 Velorum: Orbital Solution and Fundamental Parameter Determination with SUSI
• Cygnus OB2 DANCe: A high precision proper motion study of the Cygnus OB2 association
• Optimal photometry for colour-magnitude diagrams and its application to NGC 2547
• The discovery of a low mass, pre-main-sequence stellar association around gamma Velorum
• Low mass stars, brown dwarf candidates and the mass function of the young open cluster NGC 2547
• The Gaia-ESO Survey: Discovery of a spatially extended low-mass population in the Vela OB2 association
• The Gaia-ESO Survey: membership and Initial Mass Function of the Gamma Velorum cluster
• Multiple kinematical populations in Vela OB2 from Gaia DR1 data
• Protoplanetary and Transitional Disks in the Open Stellar Cluster IC 2395

Cited by in corpus (11)

• 3D mapping of young stars in the solar neighbourhood with Gaia DR2
• Expanding associations in the Vela-Puppis region: 3D structure and kinematics of the young population
• Not all stars form in clusters -- $Gaia$-DR2 uncovers the origin of OB associations
• A 3D view of the Taurus star-forming region by Gaia and Herschel: multiple populations related to the filamentary molecular cloud
• A ring in a shell: the large-scale 6D structure of the Vela OB2 complex
• The Gaia-ESO Survey: Asymmetric expansion of the Lagoon Nebula cluster NGC 6530 from GES and Gaia DR2
• A sextet of clusters in the Vela OB2 region revealed by Gaia
• Discovery of a young stellar "snake" with two dissolving cores in the solar neighborhood
• The dynamics of the γ Vel cluster and nearby Vela OB2 association
• The Structure and 3D Kinematics of Vela OB2
• The Stellar "Snake" I: Whole Structure and Properties