The Gaia-ESO survey: Discovery of a spatially extended low-mass population in the Vela OB2 association
Journal
Date Issued
2015
Author(s)
•
Jeffries, R. D.
•
•
•
Jackson, R. J.
•
Cottaar, M.
•
Spina, L.
•
Palla, F.
•
Mapelli, M.
•
Alfaro, E. J.
•
•
•
•
Klutsch, A.
•
•
Bayo, A.
•
Barrado, D.
•
Jiménez-Esteban, F.
•
Gilmore, G.
•
•
•
Allende Prieto, C.
•
•
Carraro, G.
•
Costado, M. T.
•
Jofré, P.
•
Lardo, C.
•
•
•
•
Sbordone, L.
Description
Based on data products from observations made with ESO Telescopes at the La Silla Paranal Observatory under programme ID 188.B-3002. This work was partly supported by the European Union FP7 programme through ERC grant number 320360 and by the Leverhulme Trust through grant RPG-2012-541. We acknowledge the support from INAF and Ministero dell’Istruzione, dell’Università e della Ricerca (MIUR) in the form of the grant “Premiale VLT 2012”. The results presented here are based on the work carried out during a visit at the University of Keele, and benefit from discussions held the Gaia -ESO workshops and conferences supported by the ESF (European Science Foundation) through the GREAT Research Network Programme. L.S. aknowledges the support from Project IC120009 “Millennium Institute of Astrophysics (MAS)” of Iniciativa Científica Milenio del Ministerio de Economía, Fomento y Turismo de Chile.
Abstract
The nearby (distance ~ 350-400 pc), rich Vela OB2 association, includes γ2 Velorum, one of the most massive binaries in the solar neighbourhood and an excellent laboratory for investigating the formation and early evolution of young clusters. Recent Gaia-ESO survey observations have led to the discovery of two kinematically distinct populations in the young (10-15 Myr) cluster immediately surrounding γ2 Velorum. Here we analyse the results of Gaia-ESO survey observations of NGC 2547, a 35 Myr cluster located two degrees south of γ2 Velorum. The radial velocity distribution of lithium-rich pre-main sequence stars shows a secondary population that is kinematically distinct from and younger than NGC 2547. The radial velocities, lithium absorption lines, and the positions in a colour-magnitude diagram of this secondary population are consistent with those of one of the components discovered around γ2 Velorum. This result shows that there is a young, low-mass stellar population spread over at least several square degrees in the Vela OB2 association. This population could have originally been part of a cluster around γ2 Velorum that expanded after gas expulsion or formed in a less dense environment that is spread over the whole Vela OB2 region.
Based on observations made with the ESO/VLT, at Paranal Observatory, under program 188.B-3002 (The Gaia-ESO Public Spectroscopic Survey).Table 1 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/574/L7
Volume
574
Start page
L7
Issn Identifier
0004-6361
Ads BibCode
2015A&A...574L...7S
Rights
open.access
File(s)![Thumbnail Image]()
Loading...
Name
2015_A+A_574_L7.pdf
Size
181.88 KB
Format
Adobe PDF
Checksum (MD5)
f7e7059da2fb0090ff278feaf5f5a505