Debris streams in the solar neighbourhood as relicts from the formation of the Milky Way

@article{Helmi1999DebrisSI,
  title={Debris streams in the solar neighbourhood as relicts from the formation of the Milky Way},
  author={Amina Helmi and Simon D. M. White and P. T. de Zeeuw and Hongsheng Zhao},
  journal={Nature},
  year={1999},
  volume={402},
  pages={53-55}
}
It is now generally believed that galaxies were built up through gravitational amplification of primordial fluctuations and the subsequent merging of smaller precursor structures. The stars of the structures that assembled to form the Milky Way should make up much or all of its bulge and halo, in which case one hopes to find ‘fossil’ evidence for those precursor structures in the present distribution of halo stars. Confirmation that this process is continuing came with the discovery of the… Expand

Figures from this paper

The merger that led to the formation of the Milky Way’s inner stellar halo and thick disk
TLDR
It is demonstrated that the inner halo of the Galaxy is dominated by debris from an object that at infall was slightly more massive than the Small Magellanic Cloud, and which the authors refer to as Gaia–Enceladus, which is in line with the results of galaxy formation simulations. Expand
INSIGHT INTO THE FORMATION OF THE MILKY WAY THROUGH COLD HALO SUBSTRUCTURE. I. THE ECHOS OF MILKY WAY FORMATION
We identify 10?seven for the first time?elements of cold halo substructure (ECHOS) in the volume within 17.5 kpc of the Sun in the inner halo of the Milky Way. Our result is based on the observedExpand
New Signatures of the Milky Way Formation in the Local Halo and Inner Halo Streamers in the Era of Gaia
We explore the vicinity of the Milky Way through the use of spectro-photometric data from the Sloan Digital Sky Survey and high-quality proper motions derived from multi-epoch positions extractedExpand
FASHIONABLY LATE? BUILDING UP THE MILKY WAY'S INNER HALO
Using a sample of 246 metal-poor stars (RR Lyraes, red giants, and red horizontal branch stars) which is remarkable for the accuracy of its six-dimensional kinematical data, we find, by examining theExpand
Building blocks of the Milky Way's accreted spheroid
In the $\Lambda$CDM model of structure formation, a stellar spheroid grows by the assembly of smaller galaxies, the so-called building blocks. Combining the Munich-Groningen semi-analytical model ofExpand
A box full of chocolates: The rich structure of the nearby stellar halo revealed by Gaia and RAVE
The hierarchical structure formation model predicts that stellar halos should form, at least partly, via mergers. If this was a predominant formation channel for the Milky Way's halo, imprints ofExpand
Accretion relics in the solar neighbourhood : Debris from ωCen's parent galaxy
We use numerical simulations to investigate the orbital characteristics of tidal debris from satellites whose orbits are dragged into the plane of galact ic disks by dynamical friction beforeExpand
A giant stream of metal-rich stars in the halo of the galaxy M31
TLDR
The discovery of a giant stream of metal-rich stars within the halo of the nearest large galaxy, M31 (the Andromeda galaxy), demonstrates that the epoch of galaxy building still continues, albeit at a modest rate, and that tidal streams may be a generic feature of galaxy haloes. Expand
On the kinematic detection of accreted streams in the Gaia era: a cautionary tale
The ΛCDM cosmological scenario predicts that our Galaxy should contain hundreds of stellar streams in the solar vicinity, fossil relics of the merging history of the Milky Way and more generally ofExpand
Origin of the system of globular clusters in the Milky Way
Context. The assembly history experienced by the Milky Way is currently being unveiled thanks to the data provided by the Gaia mission. It is likely that the globular cluster system of our Galaxy hasExpand
...
1
2
3
4
5
...

References

SHOWING 1-10 OF 31 REFERENCES
Fossil Signatures of Ancient Accretion Events in the Halo
The role that minor mergers have played in the formation and structure of the Milky Way is still an open question, about which there is much debate. We use numerical simulations to explore theExpand
Building up the stellar halo of the Galaxy
We study numerical simulations of satellite galaxy disruption in a potential resembling that of the Milky Way. Our goal is to assess whether a merger origin for the stellar halo would leaveExpand
Compositions of halo clusters and the formation of the galactic halo
A method of abundance determination based on reddening-independent properties of low-resolution spectral scans is described and applied to 177 red giants in 19 globular clusters, most of which are atExpand
A Dynamical and Kinematic Model of the Galactic Stellar Halo and Possible Implications for Galaxy Formation Scenarios
We reanalyze the kinematics and dynamics of the system of blue horizontal-branch field (BHBF) stars in the Galactic halo (in particular the outer halo), fitting the kinematics with the model ofExpand
A dwarf satellite galaxy in Sagittarius
WE have detected a large, extended group of comoving stars in the direction of the Galactic Centre, which we interpret as belonging to a dwarf galaxy that is closer to our own Galaxy than any otherExpand
DWARF GALAXIES OF THE LOCAL GROUP
▪ Abstract The Local Group dwarf galaxies offer a unique window to the detailed properties of the most common type of galaxy in the Universe. In this review, I update the census of Local Group dwarfsExpand
Early Evolution of the Galactic Halo Revealed from Hipparcos Observations of Metal-poor Stars
The kinematics of 122 red giant and 124 RR Lyrae stars in the solar neighborhood are studied using accurate measurements of their proper motions obtained by the Hipparcos astrometry satellite,Expand
Galaxy formation through hierarchical clustering
Analytic methods for studying the formation of galaxies by gas condensation within massive dark halos are presented. The present scheme applies to cosmogonies where structure grows throughExpand
Kinematics of Metal-poor Stars in the Galaxy. II. Proper Motions for a Large Nonkinematically Selected Sample
We present a revised catalog of 2106 Galactic stars, selected without kinematic bias and with available radial velocities, distance estimates, and metal abundances in the range -4.0 ≤ [Fe/H] ≤ 0.0.Expand
Estimation of stellar metal abundance. I - Calibration of the Ca II K index
A method for estimating the stellar metal abundances is proposed which compares measures of the equivalent width of a single feature in moderate resolution (1 A) optical spectra of stars, the Ca II KExpand
...
1
2
3
4
...