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Related papers: A "Light," Centrally-Concentrated Milky Way Halo?

200 papers

We present initial results from ``Via Lactea'', the highest resolution simulation to date of Galactic CDM substructure. It follows the formation of a Milky Way-size halo with Mvir=1.8x10^12 Msun in a WMAP 3-year cosmology, using 234 million…

Astrophysics · Physics 2010-11-05 Juerg Diemand , Michael Kuhlen , Piero Madau

We introduce a new maximum likelihood method to model the density profile of Blue Horizontal Branch and Blue Straggler stars and apply it to the Sloan Digital Sky Survey Data Release 8 (DR8) photometric catalogue. There are a large number…

Astrophysics of Galaxies · Physics 2015-05-27 A. J. Deason , V. Belokurov , N. W. Evans

The distribution of shapes of galaxies' dark halos provides a basic test for models of galaxy formation. To-date, few dark halo shapes have been measured, and the results of different methods appear contradictory. Here, we add to the sample…

Astrophysics · Physics 2007-05-23 R. P. Olling , M. R. Merrifield

Hypervelocity stars (HVSs) travel from the Galactic Centre across the dark matter halo of the Milky Way, where they are observed with velocities in excess of the Galactic escape speed. Because of their quasi-radial trajectories, they…

Astrophysics of Galaxies · Physics 2019-06-14 O. Contigiani , E. M. Rossi , T. Marchetti

Recent measurements of the Milky Way rotation curve found a sharp decline at around $15$-$20$ kpc from the center of the Galaxy, suggesting that the Galactic dark matter halo is much less massive than predicted by other dynamical tracers.…

Astrophysics of Galaxies · Physics 2025-03-11 Xiaowei Ou , Lina Necib , Andrew Wetzel , Anna Frebel , Jeremy Bailin , Micah Oeur

The Milky Way dark matter halo is formed from the accretion of smaller subhalos. These sub-units also harbor stars---typically old and metal-poor---that are deposited in the Galactic inner regions by disruption events. In this Letter, we…

Astrophysics of Galaxies · Physics 2018-01-31 Jonah Herzog-Arbeitman , Mariangela Lisanti , Piero Madau , Lina Necib

We increase the number of remote halo tracers by using blue horizontal branch (BHB) stars out to Galactocentric distances of 130 kpc. We use SDSS EDR photometry and the VLT to detect 16 BHB stars at Galactocentric distances 70 < r < 130,…

Astrophysics · Physics 2007-05-23 L. Clewley , S. J. Warren , P. C. Hewett , M. Wilkinson , W. N. Evans

We use Gaia photometry and astrometry to estimate the vertical spatial structure of the Milky Way at the Solar radius, formally accounting for sample incompleteness (the selection function) and parallax measurement uncertainty. Our results…

Astrophysics of Galaxies · Physics 2022-02-16 Andrew Everall , Vasily Belokurov , N. Wyn Evans , Douglas Boubert , Robert J. J. Grand

We use a hybrid approach that combines high-resolution simulations of the formation of a Milky Way-like halo with a semi-analytic model of galaxy formation to study the mass content of dwarf galaxies in the concordance $\Lambda$CDM…

Astrophysics · Physics 2009-06-16 Yang-Shyang Li , Amina Helmi , Gabriella De Lucia , Felix Stoehr

A simple model for the Milky Way halo is presented. It has a flat rotation curve in the inner regions, but the density falls off sharply beyond an outer edge. This truncated, flat rotation curve (TF) model possesses a rich family of simple…

Astrophysics · Physics 2008-11-26 M. I. Wilkinson , N. W. Evans

We apply a semi-analytic galaxy formation model to two high resolution cosmological N-body simulations to investigate analogues of the Milky Way system. We select these according to observed properties of the Milky Way rather than by halo…

Astrophysics of Galaxies · Physics 2015-09-30 Qi Guo , Andrew Cooper , Carlos Frenk , John Helly , Wojciech Hellwing

The origin and structure of the hot ($T\gtrsim10^6$K) gaseous halo around Milky Way (MW)-mass galaxies provide a critical test for galaxy formation models. We perform a comprehensive comparison for a sample of MW analogues from the TNG50…

The atomic hydrogen gas (HI) disk in the outer region (beyond ~10 kpc from the centre) of Milky Way can provide valuable information about the structure of the dark matter halo. The recent 3-D thickness map of the outer HI disk from the all…

Astrophysics of Galaxies · Physics 2011-02-11 Kanak Saha , Evan S. Levine , Chanda J. Jog , Leo Blitz

We exploit the first \gaia data release to study the properties of the Galactic stellar halo as traced by RR Lyrae. We demonstrate that it is possible to select a pure sample of RR Lyrae using only photometric information available in the…

Astrophysics of Galaxies · Physics 2017-12-27 G. Iorio , V. Belokurov , D. Erkal , S. E. Koposov , C. Nipoti , F. Fraternali

We report on the discovery of a new Milky Way companion stellar system located at (RA, Dec) = (22h10m43.15s, +14:56:58.8). The discovery was made using the eighth data release of SDSS after applying an automated method to search for…

Studying the trajectories of objects like stars, globular clusters or satellite galaxies in the Milky Way allows to trace the dark matter halo but requires reliable models of its gravitational potential. Realistic, yet simple and fully…

Astrophysics of Galaxies · Physics 2016-08-23 Andreas Irrgang , Benjamin Wilcox , Evan Tucker , Lucas Schiefelbein

We study the implications of galaxy formation on dark matter direct detection using high resolution hydrodynamic simulations of Milky Way-like galaxies simulated within the EAGLE and APOSTLE projects. We identify Milky Way analogues that…

We analyse systems analogous to the Milky Way (MW) in the EAGLE cosmological hydrodynamics simulation in order to deduce the likely structure of the MW's dark matter halo. We identify MW-mass haloes in the simulation whose satellite…

Astrophysics of Galaxies · Physics 2021-01-06 Shi Shao , Marius Cautun , Alis J. Deason , Carlos S. Frenk

The mass of the Milky Way is a critical quantity which, despite decades of research, remains uncertain within a factor of two. Until recently, most studies have used dynamical tracers in the inner regions of the halo, relying on…