Issue |
A&A
Volume 583, November 2015
|
|
---|---|---|
Article Number | A76 | |
Number of page(s) | 10 | |
Section | Galactic structure, stellar clusters and populations | |
DOI | https://doi.org/10.1051/0004-6361/201526575 | |
Published online | 30 October 2015 |
RAVE stars tidally stripped or ejected from the ω Centauri globular cluster⋆,⋆⋆
1
Institut Utinam, CNRS UMR 6213, Université de Franche-Comté, OSU THETA
Franche-Comté-Bourgogne, Observatoire de Besançon,
BP 1615,
25010
Besançon Cedex,
France
e-mail: jfernandez@obs-besancon.fr
2
Centro de Investigaciones de Astronomía,
AP 264, 5101-A Mérida,
Venezuela
3
Instituto de Astronomía, Universidad Nacional Autónoma de
México, Apdo. Postal
70264, 04510
México D.F.,
Mexico
4
Observatoire astronomique de Strasbourg, Université de Strasbourg,
CNRS, UMR 7550, 11 rue de l’Université, 67000
Strasbourg,
France
5
Instituto de Ciencias Nucleares, Universidad Nacional Autónoma de
México, Ap. 70-543,
04510
D.F., México, Mexico
Received: 20 May 2015
Accepted: 10 August 2015
Using six-dimensional phase-space information from the Fourth Data release of the RAdial Velocity Experiment (RAVE) over the range of Galactic longitude 240°<l< 360° and VLSR< −239 km s-1, we computed orbits for 329 RAVE stars that were originally selected as chemically and kinematically related to ω Centauri. The orbits were integrated in a Milky-Way-like axisymmetric Galactic potential, ignoring the effects of the dynamical evolution of ω Centauri due to the tidal effects of the Galaxy disk on the cluster along time. We also ignored secular changes in the Milky Way potential over time. In a Monte Carlo scheme, and under the assumption that the stars may have been ejected with velocities greater than the escape velocity (Vrel>Vesc,0) from the cluster, we identified 15 stars as having close encounters with ω Centauri: (i) 8 stars with relative velocities Vrel< 200 km s-1 may have been ejected ~200 Myr ago from ω Centauri; (ii) another group of 7 stars were identified with high relative velocity Vrel> 200 km s-1 during close encounters, and it seems unlikely that they were ejected from ω Centauri. We also confirm the link between J131340.4-484714 as a potential member of ω Centauri, and probably ejected ~2.0 Myr ago, with a relative velocity Vrel ~ 80 km s-1.
Key words: stars: abundances / stars: kinematics and dynamics / Galaxy: structure / globular clusters: individual: ωCentauri
Appendix A is available in electronic form at http://www.aanda.org
Full Table A.1 is only available at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/583/A76
© ESO, 2015
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.