Related papers: Atomic Hydrogen in a Galactic Center Outflow

Arecibo mapping is reported of the neutral hydrogen distribution along selected directions out from the centers of two small High Velocity Clouds (HVC), W486 and W491. Both HVCs have a small inner region where the neutral hydrogen column…

We report a new 1-pc (30") resolution CS($J=2-1$) line map of the central 30 pc of the Galactic Center (GC), made with the Nobeyama 45m telescope. We revisit our previous study of the extraplanar feature called polar arc (PA), which is a…

Using the 100-m radio telescope at Effelsberg, we mapped a large area around the Andromeda Galaxy in the 21-cm line emission of neutral hydrogen to search for high-velocity clouds (HVCs) out to large projected distances in excess of 100…

Using an absorption line from the metastable (J, K) = (3, 3) level of H3+ together with other lines of H3+ and CO observed along several sightlines, we have discovered a vast amount of high temperature (T ~ 250 K) and low density (n ~ 100…

Outflows up to 1500 km/s of atomic neutral hydrogen are detected in a growing number of radio galaxies. Outflows with similar velocities are also detected in ionized gas, suggesting a common origin for the extreme kinematics of these two…

Using high-resolution ultraviolet spectra obtained with the HST/Space Telescope Imaging Spectrograph (STIS) and the Far Ultraviolet Spectroscopic Explorer, we study the metallicity, kinematics, and distance of the gaseous "Outer Arm" (OA)…

We have obtained high resolution FUSE and HST/STIS echelle observations of the quasar PG 1116+215. The semi-continuous coverage of the ultraviolet spectrum over the wavelength range 916-2800 provides detections of Galactic and high velocity…

Potential condensed clouds of gas in the Galactic halo are examined in the context of the recent models of cooling, fragmenting clouds building up the baryonic mass of the Galaxy. 582 high-velocity clouds (HVCs) are defined as the potential…

The origin of our Galaxy's high-velocity clouds (HVCs) remains a mystery after many decades of effort. In this paper, we use the TNG50 simulation of the IllustrisTNG project to identify cool, dense clouds that match observations of Galactic…

An analysis of large-area CO J=3-2 maps from the James Clerk Maxwell Telescope for 12 nearby spiral galaxies reveals low velocity dispersions in the molecular component of the interstellar medium. The three lowest luminosity galaxies show a…

Observations with the Green Bank Telescope of 21cm HI emission from the high-velocity cloud Complex H suggest that it is interacting with the Milky Way. A model in which the cloud is a satellite of the Galaxy in an inclined, retrograde…

High-velocity clouds consist of cold gas that appears to be raining down from the halo to the disc of the Milky Way. Over the past fifty years, two competing scenarios have attributed their origin either to gas accretion from outside the…

We report the detection of extremely broad emission toward two molecular clumps in the Galactic central molecular zone. We have mapped the Sagittarius C complex ($-0^\circ.61 < l < -0^\circ.27$, $-0^\circ.29 < b < 0^\circ.04$) in the HCN…

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…

A head-tail high-velocity cloud (HVC) is a neutral hydrogen halo cloud that appears to be interacting with the diffuse halo medium as evident by its compressed head trailed by a relatively diffuse tail. This paper presents a sample of 116…

Compact high-velocity clouds (CHVCs) are the most distant of the HVCs in the Local Group model and would have HI volume densities of order 0.0003/cm^3. Clouds with these volume densities and the observed neutral hydrogen column densities…

Hydrodynamical simulations of jets interacting with clouds moving in the ambient medium of the host galaxy are presented. Clouds with sizes of the order of the jet diameter and smaller, crossing the path of the jet with different speeds are…

It was proposed by Blitz et al. (1999) that High Velocity Clouds (HVCs) are remnants of Local Group formation and the average distance of HVCs is 1 Mpc, which is the result of a simple dynamical calculation leading to match the observed…

We report the first evidence of molecular gas in two atomic hydrogen (HI) clouds associated with gas outflowing from the Small Magellanic Cloud (SMC). We used the Atacama Pathfinder Experiment (APEX) to detect and spatially resolve…

The recent identification of one or two sub-parsec disks of young, massive stars orbiting the ~4e6 solar mass black hole Sgr A* has prompted an "in-situ" scenario for star formation in disks of gas formed from a cloud captured from the…