Related papers: Exploring Hydrodynamic Instabilities along the Inf…
We confirm, quantify, and provide a table of the coherent velocity substructure of the Milky Way disk within 2 kpc of the Sun towards the Galactic anticenter, with 0.2 kpc resolution. We use the radial velocities of ~340,000 F-type stars…
We present HST GHRS and STIS observations of five QSOs that probe the prominent high-velocity cloud (HVC) Complex C, covering 10% of the northern sky. Based upon a single sightline measurement (Mrk 290), a metallicity [S/H]=-1.05+/-0.12 has…
We present a study of the filamentary structure in the emission from the neutral atomic hydrogen (HI) at 21 cm across velocity channels in the 40'' and 1.5-km/s resolution position-position-velocity cube resulting from the combination of…
We study the properties of low-column density gas clumps in the halo of the Milky Way based on high-resolution 21-cm observations. Using interferometric data from the WSRT and the VLA we study HI emission at low-, intermediate- and high…
The results of the interaction between the Milky Way and the Magellanic Clouds are revealed through several high velocity complexes which are connected to the Clouds. The exact mechanism of their formation is under some debate, but they…
We report the discovery of two kinematically anomalous atomic hydrogen (HI) clouds in M 100 (NGC 4321), which was observed as part of the Deciphering the Interplay between the Interstellar medium, Stars, and the Circumgalactic medium…
There is evidence in 21cm HI emission for voids several kpc in size centered approximately on the Galactic centre, both above and below the Galactic plane. These appear to map the boundaries of the Galactic nuclear wind. An analysis of HI…
The narrow GD-1 stream of stars, spanning 60 deg on the sky at a distance of ~10 kpc from the Sun and ~15 kpc from the Galactic center, is presumed to be debris from a tidally disrupted star cluster that traces out a test-particle orbit in…
We report the first determination of a distance bracket for the high-velocity cloud (HVC) complex C. Combined with previous measurements showing that this cloud has a metallicity of 0.15 times solar, these results provide ample evidence…
FAST HI observations reveal unprecedented internal structures of the high-velocity cloud AC-III, which is found to consist of several coherent subclumps (D1-D6) with nearly constant line widths of $\sim 20~\mathrm{km~s^{-1}}$, while the…
We present a catalog of 3D Galactic HI filaments over 1/3 of the sky using Galactic Arecibo L-band Feed Array HI (GALFA-HI) data. The 3D filaments are defined to be linear HI features that are continuous in position-position-velocity (PPV)…
Using Milky Way data of the new Effelsberg-Bonn HI Survey (EBHIS) and the Galactic All-Sky Survey (GASS), we present a revised picture of the high-velocity cloud (HVC) complex Galactic Center Negative (GCN). Owing to the higher angular…
Neutral hydrogen clouds are found in the Milky Way and Andromeda halo both as large complexes and smaller isolated clouds. Here we present a search for Hi clouds in the halo of M33, the third spiral galaxy of the Local Group. We have used…
We present a panoramic map of the stellar streams of the Milky Way based upon astrometric and photometric measurements from the Gaia DR2 catalogue. In this first contribution, we concentrate on the halo at heliocentric distances beyond 5…
21-cm HI4PI survey data are used to study the anomalous-velocity hydrogen gas associated with high-velocity cloud Complex M. These high-sensitivity, high-resolution, high-dynamic-range data show that many of the individual features,…
The Galactic Arecibo L-band Feed Array HI (GALFA-HI) survey is mapping the entire Arecibo sky at 21-cm, over a velocity range of -700 to +700 km/s (LSR), at a velocity resolution of 0.18 km/s and an angular resolution of 3.5 arcmin. The…
We present a new measurement, 0.85-3.5 Z_solar, of the metallicity of high velocity cloud (HVC) Complex M by analyzing ultraviolet spectroscopic observations of the blazar Mrk 421 taken with the Cosmic Origins Spectrograph on the Hubble…
We investigated a hydrostatic equilibrium model of the Milky Way following Parker (1966), to constrain the large scale properties of the interstellar medium. In our approach we found an excellent agreement between our simple hydrostatic…
A3667, a spectacular merger cluster, was observed by Chandra twice. In this paper we review the main results of the analysis of these observations. In particular we show evidence for the presence in the cluster of a 300 kpc Kelvin-Helmholtz…
Numerical simulations have explored the possibility to form molecular clouds through either a quasi-static, self-gravitating mechanism or the collision of gas streams or lower-density clouds. They also quantitatively predict the…