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Related papers: Formation Scenarios

200 papers

Near-field observations may provide tight constraints - i.e. "boundary conditions" - on any model of structure formation in the Universe. Detailed observational data have long been available for the Milky Way (e.g. Freeman $\&$…

Astrophysics of Galaxies · Physics 2015-06-16 Agostino Renda

The manner the galaxy accretes matter along with the star formation rates at different epochs, influence the evolution of the stable isotopic inventories of the galaxy. A detailed analysis is presented here to study the dependence of the…

Astrophysics of Galaxies · Physics 2014-08-05 S. Sahijpal

Current ideas on the formation of the Galaxy are reviewed. Many of the observed characteristics of our Milky Way System are consistent with a scenario in which the Galaxy formed inside out, with the inner part of it evolving by rapid…

Astrophysics · Physics 2009-10-28 Sidney van den Bergh

The Milky Way is a spiral galaxy comprising three main components: the Bulge, the Disk, and the Halo. Of particular interest is the Galactic disk, which holds a significant portion of the baryonic matter angular momentum and harbors at…

Astrophysics of Galaxies · Physics 2024-02-13 Maria Rah , Manolya Yatman , Ali Taani , Ahmad A. Abushattal , Mohammad K. Mardini

We present results from \textsc{GigaEris}, a cosmological, $N$-body hydrodynamical "zoom-in" simulation of the formation of a Milky Way-sized galaxy halo with unprecedented resolution, encompassing of order a billion particles within the…

Astrophysics of Galaxies · Physics 2022-04-06 Tomas Tamfal , Lucio Mayer , Thomas R. Quinn , Arif Babul , Piero Madau , Pedro R. Capelo , Sijing Shen , Marius Staub

We examine metallicities, ages and orbital properties of halo stars in a Milky-Way like disk galaxy formed in the cosmological hydrodynamical MaGICC simulations. Halo stars were either accreted from satellites or they formed in situ in the…

Astrophysics of Galaxies · Physics 2016-09-07 Monica Valluri , Sarah R. Loebman , Jeremy Bailin , Adam Clarke , Victor P. Debattista , Greg Stinson

Stellar halos of galaxies retain crucial clues to their mass assembly history. It is in these galactic components that the remains of cannibalised galactic building blocks are deposited. For the case of the Milky Way, the opportunity to…

Astrophysics of Galaxies · Physics 2024-04-29 Danny Horta , Ricardo P. Schiavon

We perform numerical simulations for the formation of the Galactic stellar halo, based on the currently favored cold dark matter (CDM) theory of galaxy formation. Our numerical models, taking into account both dynamical and chemical…

Astrophysics · Physics 2009-11-06 Kenji Bekki , Masashi Chiba

Small stellar systems like dwarf galaxies are suggested to be the main building blocks of our Galaxy by numerical simulations in Lambda CDM models. The existence of star streams like Sagittarius tidal stream indicates that dwarf galaxies…

Solar and Stellar Astrophysics · Physics 2019-05-13 Qian-Fan Xing , Gang Zhao , Wako Aoki , Satoshi Honda , Hai-Ning Li , Miho N. Ishigaki , Tadafumi Matsuno

As galaxies form hierarchically, larger satellites may accrete alongside smaller companions in group infall events. This coordinated accretion is likely to have left signatures in the Milky Way's stellar halo at the present day. Our goal is…

Astrophysics of Galaxies · Physics 2025-08-20 Thomas M. Callingham , Amina Helmi

In chemodynamical evolution models it is usually assumed that the Milky Way galaxy forms from the inside-out implying that gas inflows onto the disk decrease with galactocentric distance. Similarly, to reproduce differences between chemical…

In the $\Lambda$-Cold Dark Matter model of the Universe, galaxies form in part through accreting satellite systems. Previous work have built an understanding of the signatures of these processes contained within galactic stellar halos. This…

We study the formation of stellar haloes in three Milky Way-mass galaxies using cosmological smoothed particle hydrodynamics simulations, focusing on the subset of halo stars that form in situ, as opposed to those accreted from satellites.…

Astrophysics of Galaxies · Physics 2015-10-28 Andrew P. Cooper , Owen H. Parry , Ben Lowing , Shaun Cole , Carlos Frenk

We study the possibility that the Milky Way's cool stellar disc includes mergers with ancient stars. Galaxies are understood to form in a hierarchical manner, where smaller (proto-)galaxies merge into larger ones. Stars in galaxies, like…

Astrophysics of Galaxies · Physics 2022-07-27 Diane K. Feuillet , Sofia Feltzing , Christian Sahlholdt , Thomas Bensby

Late accretion models for formation of the Galactic halo require that many Galactic satellite galaxies have been cannibalised into the halo field. Comparison of the metallicity and age distribution function of stars in the surviving…

Astrophysics · Physics 2019-08-17 Gerard Gilmore , Xavier Hernandez , David Valls-Gabaud

If the Galaxy formed hierarchically through the accretion of smaller satellite galaxies we might hope to find signatures of this in the halo's phase-space distribution. I review theoretical ideas about what form these signatures should…

Astrophysics · Physics 2007-05-23 Kathryn V. Johnston

A new view on our Galaxy has recently emerged, with large consequences on its formation scenarios. Not only new dwarf satellites have been detected, still orbiting and tidally disrupting, but also a multitude of stellar streams or tidal…

Astrophysics · Physics 2007-05-23 F. Combes

I briefly review the growing evidence that thick stellar disks surround most edge-on disk galaxies. Recent studies show that these extragalactic thick disks have old ages, low metallicities, long scale lengths, and moderately flattened…

Astrophysics · Physics 2007-05-23 Julianne J. Dalcanton , Anil Seth , Peter Yoachim

We analyse the chemical properties of a set of solar vicinity stars, and show that the small dispersion in abundances of \alpha-elements at all ages provides evidence that the SFH has been uniform throughout the thick disk. In the context…

Astrophysics of Galaxies · Physics 2015-04-13 M. Haywood , P. Di Matteo , O. Snaith , M. Lehnert

We present simulations of the formation of thick disks via the accretion of two-component satellites onto a pre-existing thin disk. Our goal is to establish the detailed characteristics of the thick disks obtained in this way, as well as…

Astrophysics · Physics 2008-09-19 Álvaro Villalobos , Amina Helmi