Related papers: Detecting Halo Streams with GAIA
We develop a framework for modelling the Milky Way using stellar streams and a wide range of photometric and kinematic observations. Through the use of mock data we demonstrate that a standard suite of Galactic observations leads to…
We develop statistical methods for identifying star streams in the halo of the Milky Way galaxy that exploit observed spatial and radial velocity distributions. Within a great circle, departures of the observed spatial distribution from…
Based on the second Gaia data release (Gaia DR2) and spectroscopy from the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) Data, we identified 20,089 halo stars kinematically and chemically. The halo streams in the solar…
One of the generic predictions of modern cosmological models is that large galaxies should have experienced many mergers with smaller galaxies at some point in their past. Debris from such encounters will leave spatially distinct…
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…
Narrow stellar streams in the Milky Way halo are uniquely sensitive to dark-matter subhalos, but many of these subhalos may be tidally disrupted. I calculate the interaction between stellar and dark-matter streams using analytical and…
The Gaia mission promises to deliver precision astrometry at an unprecedented level, heralding a new era for discerning the kinematic and spatial coordinates of stars in our Galaxy. Here, we present a new technique for estimating the age of…
Stellar haloes form through the disruption of satellite galaxies over time, making them a promising observable for constraining galaxy merger histories. We use a dynamical decomposition technique to isolate the stellar haloes of Milky…
The $\Lambda$CDM cosmological scenario predicts that our Galaxy should contain hundreds of stellar streams at the solar vicinity, fossil relics of the merging history of the Milky Way and more generally of the hierarchical growth of…
Mergers and tidal interactions between massive galaxies and their dwarf satellites are a fundamental prediction of the Lambda-Cold Dark Matter cosmology. These events are thought to influence galaxy evolution throughout cosmic history and…
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 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 extracted from the Guide Star Catalogue II database.…
The halo of the Milky Way has long been hypothesized to harbour significant amounts of merger debris. This view has been supported over more than a decade by wide-field photometric surveys which have revealed the outer halo to be lumpy. The…
Our 'home galaxy' - the Milky Way - is a fairly large spiral galaxy, prototype of the most common morphological class in the local Universe. Although being only a galaxy, it is the only one that can be studied in unique detail: for the…
We present quantitative statistical evidence for a $\gamma$-ray emission halo surrounding the Galaxy. Maps of the emission are derived. EGRET data were analyzed in a wavelet-based non-parametric hypothesis testing framework, using a model…
We present a Field of Streams visualizing stellar structures in the Milky Way halo as viewed by the Dark Energy Camera (DECam). We use $g$- and $r$-band imaging from the Dark Energy Survey and the DECam Legacy Survey, covering $18{,}700…
Stellar streams result from the tidal disruption of satellites and star clusters as they orbit a host galaxy, and can be very sensitive probes of the gravitational potential of the host system. We select and study narrow stellar streams…
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…
The relics of disrupted satellite galaxies around the Milky Way and Andromeda have been found, but direct evidence of a satellite galaxy in the early stages of being disrupted has remained elusive. We have discovered a dwarf satellite…
We have simulated the evolution of tidal debris in the Galactic halo in order to guide our ongoing survey to determine the fraction of halo mass accreted via satellite infall. Contrary to naive expectations that the satellite debris will…