Expanding associations in the Vela-Puppis region. 3D structure and kinematics of the young population
Journal
Date Issued
2019
Author(s)
Cantat-Gaudin, T.
•
Jordi, C.
•
Wright, N. J.
•
Armstrong, J. J.
•
•
Balaguer-Núñez, L.
•
Ramos, P.
•
Bossini, D.
•
Padoan, P.
•
Pelkonen, V. M.
•
Mapelli, M.
•
Jeffries, R. D.
Abstract
Context. The Vela-Puppis region is known to host the Vela OB2 association as well as several young clusters featuring OB and pre-main-sequence stars. Several spatial and kinematic subgroups have been identified in recent years.
Aims: By grouping stars based on their positions and velocity, we can address the question of the dynamical history of the region and the mechanisms that drove stellar formation. The Gaia DR2 astrometry and photometry enables us to characterise the 3D spatial and 3D kinematic distribution of young stars and to estimate the ages of the identified components.
Methods: We used an unsupervised classification method to group stars based on their proper motions and parallax. We studied the expansion rates of the different identified groups based on 3D velocities and on corrected tangential velocities. We used theoretical isochrones to estimate ages.
Results: The young stars can be separated into seven main groups of different ages and kinematical distribution. All groups are found to be expanding, although the expansion is mostly not isotropic.
Conclusions: The size of the region, the age substructure, and the anisotropic expansion rates are compatible with a prolonged period of star formation in a turbulent molecular cloud. The current kinematics of the stars cannot be explained by internal processes alone (such as gas expulsion).
Aims: By grouping stars based on their positions and velocity, we can address the question of the dynamical history of the region and the mechanisms that drove stellar formation. The Gaia DR2 astrometry and photometry enables us to characterise the 3D spatial and 3D kinematic distribution of young stars and to estimate the ages of the identified components.
Methods: We used an unsupervised classification method to group stars based on their proper motions and parallax. We studied the expansion rates of the different identified groups based on 3D velocities and on corrected tangential velocities. We used theoretical isochrones to estimate ages.
Results: The young stars can be separated into seven main groups of different ages and kinematical distribution. All groups are found to be expanding, although the expansion is mostly not isotropic.
Conclusions: The size of the region, the age substructure, and the anisotropic expansion rates are compatible with a prolonged period of star formation in a turbulent molecular cloud. The current kinematics of the stars cannot be explained by internal processes alone (such as gas expulsion).
The list of members of the young populations established in this study is only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/626/A17
Volume
626
Start page
A17
Issn Identifier
0004-6361
Ads BibCode
2019A&A...626A..17C
Rights
restricted
File(s)![Thumbnail Image]()
![Thumbnail Image]()
Loading...
Name
aa34957-18.pdf
Description
pdf editoriale
Size
32.13 MB
Format
Adobe PDF
Checksum (MD5)
990d2929bae05190aff96da31ef95a46
Loading...
Name
29645-aa34957-18_P05.pdf
Description
Miur
Size
7.81 MB
Format
Adobe PDF
Checksum (MD5)
111d75728c8a32feb2ae69bf78fb099d