The Gaia-ESO Survey: a quiescent Milky Way with no significant dark/stellar accreted disc★
Authors:
- G. R. RuchtiGRG. R. Ruchti
- J. I. ReadJRJ. I. Read
- S. FeltzingSFS. Feltzing
- A. M. SerenelliASA. M. Serenelli
- P. McMillanPMP. McMillan
- K. LindKLK. Lind
- T. BensbyTBT. Bensby
- M. BergemannMBM. Bergemann
- M. AsplundMAM. Asplund
- A. VallenariAVA. Vallenari
- E. FlaccomioEFE. Flaccomio
- E. PancinoEPE. Pancino
- 11 May 2015
- journal article
- research article
- Published by Oxford University Press (OUP) in Monthly Notices of the Royal Astronomical Society
- Vol. 450 (3) , 2874-2887
Abstract
According to our current cosmological model, galaxies like the Milky Way are expected to experience many mergers over their lifetimes. The most massive of the merging galaxies will be dragged towards the disc plane, depositing stars and dark matter into an accreted disc structure. In this work, we utilize the chemodynamical template developed in Ruchti et al. to hunt for accreted stars. We apply the template to a sample of 4675 stars in the third internal data release from the Gaia-ESO Spectroscopic Survey. We find a significant component of accreted halo stars, but find no evidence of an accreted disc component. This suggests that the Milky Way has had a rather quiescent merger history since its disc formed some 8–10 billion years ago and therefore possesses no significant dark matter disc.Keywords
All Related Versions
This publication has 85 references indexed in Scilit:
- TheGaia-ESO Survey: radial metallicity gradients and age-metallicity relation of stars in the Milky Way diskAstronomy & Astrophysics, 2014
- Exploring the Milky Way stellar diskAstronomy & Astrophysics, 2014
- Chemical evolution of the Galactic bulge as traced by microlensed dwarf and subgiant starsAstronomy & Astrophysics, 2013
- Chemical evolution of the Galactic bulge as traced by microlensed dwarf and subgiant starsAstronomy & Astrophysics, 2011
- An abundance study of red-giant-branch stars in the Hercules dwarf spheroidal galaxyAstronomy & Astrophysics, 2010
- The Chemical Composition of the SunAnnual Review of Astronomy and Astrophysics, 2009
- Disentangling the Hercules StreamThe Astrophysical Journal, 2007
- A Spectroscopic Study of the Ancient Milky Way: F‐ and G‐Type Stars in the Third Data Release of the Sloan Digital Sky SurveyThe Astrophysical Journal, 2006
- Simulations of Galaxy Formation in a Λ Cold Dark Matter Universe. II. The Fine Structure of Simulated Galactic DisksThe Astrophysical Journal, 2003
- A Search for Stars of Very Low Metal Abundance. V. Photoelectric [ITAL]UBV[/ITAL] Photometry of Metal-weak Candidates from the Northern HK SurveyThe Astronomical Journal, 2000