English

RAVE stars tidally stripped/ejected from $\omega$ Centauri globular cluster

Astrophysics of Galaxies 2015-11-04 v1

Abstract

Using six-dimesional phase-space information from the Fourth Data release of the Radial Velocity Experiment (RAVE) over the range of Galactic longitude 240<l<^{\circ}< l < 360^{\circ} and VLSR<239V_{LSR} < -239 kms1^{-1}, we have computed orbits for 329 RAVE stars that were originally selected as chemically and kinematically related to ω\omega Centauri. The orbits were integrated in a Milky-Way-like axisymmetric Galactic potential, ignoring the effects of the dynamical evolution of ω\omega 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,0V_{rel}>V_{esc,0}) from the cluster, we identified 15 stars as having close encounters with ω\omega Centauri: (\textit{i}) 8 stars with relative velocities Vrel<200V_{rel}< 200 kms1^{-1} may have been ejected \sim 200 Myr ago from ω\omega Centauri; (\textit{ii}) other group of 7 stars were identified with high relative velocity Vrel>200V_{rel}> 200 kms1^{-1} during close encounters, and seems unlikely that they have been ejected from ω\omega Centauri. We also confirm the link between J131340.4-484714 as potential member of ω\omega Centauri, and probably ejected \sim 2.0 Myr ago, with a relative velocity Vrel80V_{rel}\sim80 kms1^{-1}.

Keywords

Cite

@article{arxiv.1508.02839,
  title  = {RAVE stars tidally stripped/ejected from $\omega$ Centauri globular cluster},
  author = {J. G. Fernández-Trincado and A. C. Robin and K. Vieira and E. Moreno and O. Bienaymé and C. Reylé and O. Valenzuela and B. Pichardo and F. Robles-Valdez and A. M. M. Martins},
  journal= {arXiv preprint arXiv:1508.02839},
  year   = {2015}
}

Comments

10 pages, 8 figures, accepted for publication in Astron. and Astrophys

R2 v1 2026-06-22T10:31:51.928Z