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Related papers: Dark Galactic subhalos and the Gaia snail

200 papers

This study presents a tomographic survey of a subset of the outer halo (10-40 kpc) drawn from the Sloan Digital Sky Survey Data Release 6. Halo substructure on spatial scales of $>3$ degrees is revealed as an excess in the local density of…

Astrophysics of Galaxies · Physics 2015-05-14 Stefan C. Keller

There is increasing evidence that a substantial fraction of Milky Way satellite galaxies align in a rotationally-supported plane of satellites, a rare configuration in cosmological simulations of galaxy formation. It has been suggested that…

Astrophysics of Galaxies · Physics 2020-04-23 Alexander H. Riley , Louis E. Strigari

We use high-resolution numerical simulations to study the physical properties of subhalos when they merge into their host halos. An improved algorithm is used to identify the subhalos. We then examine their spatial and velocity…

Astrophysics · Physics 2009-11-11 H. Y. Wang , Y. P. Jing , Shude Mao , Xi Kang

The lack of tangible evidence for non-gravitational interactions between dark and visible sectors drives the need for exploring new avenues of inferring dark matter properties through purely gravitational probes. In particular, addressing…

Astrophysics of Galaxies · Physics 2021-02-23 Mihael Petac

We present quantitative predictions for the detectability of individual Galactic dark matter subhalos in gamma-rays from dark matter pair annihilations in their centers. Our method is based on a hybrid approach, employing the highest…

Astrophysics · Physics 2009-11-13 Michael Kuhlen , Jürg Diemand , Piero Madau

The existence of stellar halos around galaxies is a natural prediction of the hierarchical nature of the LambdaCDM model. Recent observations of Milky Way-like galaxies have revealed a wide range in stellar halo mass, including cases with…

Two studies have recently reported the discovery of pronounced Halo substructure in the Sloan Digital Sky Survey (SDSS) commissioning data. Here we show that this Halo substructure is almost in its entirety due to the expected tidal stream…

Astrophysics · Physics 2009-05-29 Rodrigo Ibata , Michael Irwin , Geraint Lewis , Andrea Stolte

The density-wave theory of spiral structure proposes that star formation occurs in or near a spiral-shaped region of higher density that rotates rigidly within the galactic disk at a fixed pattern speed. In most interpretations of this…

The Milky Way halo is one of the few galactic haloes that provides a unique insight into galaxy formation by resolved stellar populations. Here, we present a catalogue of $\sim$47 million halo stars selected independent of parallax and…

We obtain predictions for the properties of cold dark matter annihilation radiation using high resolution hydrodynamic zoom-in cosmological simulations of Milky Way-like galaxies (APOSTLE project) carried out as part of the "Evolution and…

Most fully developed galaxies have a vivid spiral structure, but the formation and evolution of the spiral structure are still an enigma in astrophysics. In this paper, according to the standard Newtonian gravitational theory and some…

General Physics · Physics 2009-05-16 Ying-Qiu Gu

We describe our recent attempts to model substructure in dark matter halos down to very small masses, using a semi-analytic model of halo formation. The results suggest that numerical simulations of halo formation may still be missing…

Astrophysics · Physics 2007-05-23 James E. Taylor , Arif Babul , Joseph Silk

We present preliminary results of a long-term project to investigate the process of accretion and tidal disruption of dSph satellites in the Galactic halo and, in particular, to search for new tidal tails in a sample of nearby dSph…

Astrophysics · Physics 2009-10-31 D. Martinez-Delgado , A. Aparicio , M. A. Gomez-Flechoso

Aims. Several kinematic and chemical substructures have been recently found amongst Milky Way halo stars with retrograde motions. It is currently unclear how these various structures are related to each other. This Letter aims to shed light…

Astrophysics of Galaxies · Physics 2019-11-13 Helmer H. Koppelman , Amina Helmi , Davide Massari , Adrian M. Price-Whelan , Tjitske K. Starkenburg

The observed population of the Milky Way satellite galaxies offer a unique testing ground for galaxy formation theory on small-scales. Our novel approach was to investigate the clustering of the known Milky Way satellite galaxies and to…

Astrophysics of Galaxies · Physics 2015-06-16 Brandon Bozek , Rosemary F. G. Wyse , Gerard Gilmore

The last 10-20 years has seen a profound shift in views of how the Galaxy's halo formed. The idea of a monolithic early collapse of a single system (Eggen, Lynden-Bell and Sandage 1962) has been challenged by observations at high redshift…

It has been recently claimed that the confined structure of the debris from the Sagittarius dwarf implies that the dark-matter halo of our Galaxy should be nearly spherical, in strong contrast with predictions from cold dark-matter (CDM)…

Astrophysics · Physics 2009-11-10 Amina Helmi

The morphology and kinematics of the spiral structure of the Milky Way is a long-standing problem in astrophysics. In this review we firstly summarize various methods with different tracers used to solve this puzzle. The astrometry of…

Astrophysics of Galaxies · Physics 2019-01-16 Ye Xu , Ligang Hou , Yuanwei Wu

As the Milky Way and its satellite system become more entrenched in near field cosmology efforts, the need for an accurate mass estimate of the Milky Way's dark matter halo is increasingly critical. With the second and early third data…

The inference of the Milky Way halo mass requires modelling the phase space structure of dynamical tracers, with different tracers following different models and having different levels of sensitivity to the halo mass. For steady-state…

Astrophysics of Galaxies · Physics 2020-05-20 Jiaxin Han , Wenting Wang , Zhaozhou Li