English
Related papers

Related papers: Galactic stellar haloes in the CDM model

200 papers

We analyze the orbits of stars and dark matter particles in the halo of a disk galaxy formed in a cosmological hydrodynamical simulation. The halo is oblate within the inner ~20 kpc and triaxial beyond this radius. About 43% of orbits are…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Monica Valluri , Victor P. Debattista , Gregory S. Stinson , Jeremy Bailin , Thomas R. Quinn , H. M. P. Couchman , James Wadsley

The Galactic stellar halo is predicted to have formed at least partially from the tidal disruption of accreted dwarf galaxies. This assembly history should be detectable in the orbital and chemical properties of stars. The H3 Survey is…

A fundamental prediction of the Lambda Cold Dark Matter (LCDM) cosmology is the centrally divergent cuspy density profile of dark matter haloes. Density cusps render CDM haloes resilient to tides, and protect dwarf galaxies embedded in them…

Astrophysics of Galaxies · Physics 2024-06-14 Raphaël Errani , Rodrigo Ibata , Julio F. Navarro , Jorge Peñarrubia , Matthew G. Walker

We investigate the formation and evolution of satellite galaxies using smoothed particle hydrodynamics (SPH) simulations of a Milky Way(MW)-like system, focussing on the best resolved examples, analogous to the classical MW satellites.…

Astrophysics of Galaxies · Physics 2015-05-28 Owen H. Parry , Vincent R. Eke , Carlos S. Frenk , Takashi Okamoto

The recent advent of deep observational surveys of local Milky Way `analogues' and their satellite populations allows us to place the Milky Way in a broader cosmological context and to test models of galaxy formation on small scales. In the…

Astrophysics of Galaxies · Physics 2021-05-26 Andreea S. Font , Ian G. McCarthy , Vasily Belokurov

We present a new technique for creating mock catalogues of the individual stars that make up the accreted component of stellar haloes in cosmological simulations and show how the catalogues can be used to test and interpret observational…

Astrophysics of Galaxies · Physics 2014-11-27 Ben Lowing , Wenting Wang , Andrew Cooper , Rachel Kennedy , John Helly , Carlos Frenk , Shaun Cole

Accreted stars in the Milky Way (MW) preserve information about the progenitor galaxies where they formed in their chemical and kinematic properties. In this study, we use the chemo-dynamical signatures in the merger debris to approximate…

Astrophysics of Galaxies · Physics 2026-03-16 Andrea Sante , Andreea S. Font , Daisuke Kawata , T. Lucas Makinen , Robert J. J. Grand

In hierarchical structure formation, dark matter halos that merge with larger halos can persist as subhalos. These subhalos are likely hosts of visible galaxies. While the dense halo environment rapidly strips subhalos of their dark mass,…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Andrew R. Wetzel , Martin White

Dwarf galaxies have a wide variety of structures, such as dark matter (DM) distribution, stellar-to-halo mass ratio, and stellar density. Recent high-resolution simulations have shown a variety of stellar-to-halo mass ratios for dwarf…

Astrophysics of Galaxies · Physics 2026-01-21 Katsuhiro Kaneko , Takayuki R. Saitoh , Yutaka Hirai , Michiko S. Fujii

Since the chemical abundances of stars are the fossil records of the physical conditions in galaxies, they provide the key information for recovering the assembly history of galaxies. In this work, we explore the chemo-chrono-kinematics of…

We use N-body simulations to model the tidal evolution of dark matter-dominated dwarf spheroidal galaxies embedded in cuspy Navarro-Frenk-White subhalos. Tides gradually peel off stars and dark matter from a subhalo, trimming it down…

Astrophysics of Galaxies · Physics 2022-03-18 Raphaël Errani , Julio F. Navarro , Rodrigo Ibata , Jorge Peñarrubia

The dwarf satellite galaxies of the Milky Way Crater II and Antlia II have uncommonly low dynamical mass densities, due to their large size and low velocity dispersion. Previous work have failed to identify formation scenarios within the…

Astrophysics of Galaxies · Physics 2019-08-14 Nicola C. Amorisco

We use numerical simulations to examine the substructure within galactic and cluster mass halos that form within a hierarchical universe. Clusters are easily reproduced with a steep mass spectrum of thousands of substructure clumps that…

We present a new model for the formation of stellar halos in dwarf galaxies. We demonstrate that the stars and star clusters that form naturally in the inner regions of dwarfs are expected to migrate from the gas rich, star forming centre…

Astrophysics of Galaxies · Physics 2012-08-10 Aaron J. Maxwell , James Wadsley , H. M. P. Couchman , Sergey Mashchenko

We present the first and so far the only simulations to follow the fine-grained phase-space structure of galaxy haloes formed from generic LCDM initial conditions. We integrate the geodesic deviation equation in tandem with the N-body…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Mark Vogelsberger , Simon D. M. White

Galaxies can form in a sufficiently deep gravitational potential so that efficient gas cooling occurs. We estimate that such potential is provided by a halo of mass $M \gtsim M_{c} \approx 7.0 \times 10^{12} ~ (\Delta_{c}(z)…

Astrophysics · Physics 2009-09-07 Hung-Yu Jian , Chia-Hung Chien , Tzihong Chiueh

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

Simulations of tidal streams show that close encounters with dark matter subhalos induce density gaps and distortions in on-sky path along the streams. Accordingly, observing disrupted streams in the Galactic halo would substantiate the…

Astrophysics of Galaxies · Physics 2017-07-26 Emily Sandford , Andreas H. W. Kuepper , Kathryn V. Johnston , Juerg Diemand

The accreted component of stellar halos is composed of the contributions of several satellites, falling onto their host with their different masses, at different times, on different orbits. This work uses a suite of idealised, collisionless…

Astrophysics of Galaxies · Physics 2016-09-21 N. C. Amorisco

We use the ``Via Lactea'' simulation to study the co-evolution of a Milky Way-size LambdaCDM halo and its subhalo population. While most of the host halo mass is accreted over the first 6 Gyr in a series of major mergers, the physical mass…

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