English
Related papers

Related papers: Summary of Recent Progress in Understanding HVCs

200 papers

The high-velocity clouds (HVCs) in the outer Milky Way at $20^{\circ} < l < 190^{\circ}$ have similar spatial locations, metallicities, and kinematics. Moreover, their locations and kinematics are coincident with several extraplanar stellar…

Astrophysics of Galaxies · Physics 2022-10-21 Todd M. Tripp

We have undertaken high-resolution follow-up of a sample of high velocity HI clouds apparently associated with M31. Our sample was chosen from the population of high-velocity clouds (HVCs) detected out to 50 kpc projected radius of the…

Astrophysics · Physics 2009-11-10 T. Westmeier , R. Braun , D. Thilker

We present new observational results on high-velocity clouds (HVCs) based on an analysis of the Leiden/Dwingeloo HI survey. We cataloged all HVCs with NHI > 1 10^19 cm^-2 and found 252 clouds that form a representative flux limited sample.…

Astrophysics · Physics 2007-05-23 C. Bruens , J. Kerp , P. M. W. Kalberla , U. Mebold

Recent observations of high velocity clouds (HVCs) have revealed compression fronts and tail shaped features of HI suggesting that they are interacting with external medium. We perform 3-D hydro-dynamical simulations of HVCs moving through…

Astrophysics · Physics 2009-11-06 Vicent Quilis , Ben Moore

High-Velocity Clouds (HVCs) have radial velocities that cannot be explained by the global Galactic rotation; their distances remain mostly unknown, and their true nature and origin are still a mystery. Some of them could be of galactic…

Astrophysics · Physics 2007-05-23 F. Combes , V. Charmandaris

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…

Astrophysics of Galaxies · Physics 2015-05-30 M. E. Putman , D. R. Saul , E. Mets

We present a high-resolution study of five high-velocity clouds in the Magellanic Leading Arm region. This is a follow-up study of our widefield Parkes survey of the region in order to probe the multiphase structures of the clouds and to…

Astrophysics of Galaxies · Physics 2016-06-15 B. Q. For , L. Staveley-Smith , N. M. McClure-Griffiths , T. Westmeier , K. Bekki

High Velocity Clouds (HVCs) have recently attracted renewed attention as being long lived, massive dark matter dominated clouds of primordial composition distributed throughout the Local Group. In this picture the HVCs would contain a few…

Astrophysics · Physics 2007-05-23 Martin A. Zwaan

We present observations of the (field of the) Seyfert galaxy Mark290, which probes the high-velocity cloud (HVC) complex C, one of the largest HVCs. We find that this object has a metallicity of 0.094pm0.020(+0.022-0.019) times solar. We…

Our view of the high velocity cloud (HVC) system is changing dramatically with new observations from the Far Ultraviolet Spectroscopic Explorer mission and the Space Telescope Imaging Spectrograph onboard the Hubble Space Telescope. In…

Astrophysics · Physics 2007-05-23 Kenneth R. Sembach

High-velocity clouds (HVCs) are clouds of HI seen around the Milky Way with velocities inconsistent with Galactic rotation, have unknown distances and masses and controversial origins. One possibility is that HVCs are associated with the…

High-velocity clouds (HVCs) are interstellar gas clouds whose velocities are incompatible with Galactic rotation. Since the first discovery of HVCs in 1963, their origins have been debated for decades but are still not settled down, because…

Astrophysics of Galaxies · Physics 2025-06-19 Yu-Ting Wang , Chao Liu , Zhi-Yu Zhang

We have detected absorption lines from the High Velocity Cloud Complex WB in the spectrum of the star HE1048+0231. This detection sets an upper distance limit to the cloud of 8.8^{+2.3}_{-1.3} kpc. Non-detection (at >4 sigma confidence) in…

Astrophysics · Physics 2009-11-11 C. Thom , M. E. Putman , B. K. Gibson , N. Christlieb , C. Flynn , T. C. Beers , R. Wilhelm , Y. S. Lee

From an analysis of the sky and velocity distributions of the high-velocity clouds (HVCs) we show that the majority of the HVCs has a common origin. We conclude that the HVCs surround the Galaxy, forming a metacloud of 300 kpc in size and…

Astrophysics · Physics 2009-11-11 Carlos A. Olano

We show 21-cm line profiles in the direction of stars and extragalactic objects, lying projected on high- and intermediate-velocity clouds (HVCs and IVCs). About half of these are from new data obtained with the Effelsberg 100-m telescope,…

Astrophysics · Physics 2009-11-06 B. P. Wakker , P. M. W. Kalberla , H. van Woerden , K. S. de Boer , M. E. Putman

Growing evidence supports the suggestion that the compact high-velocity clouds of HI (CHVCs) are located throughout the Local Group and continue to fuel galactic evolution. Recent distance estimates to individual objects lie in the range…

Astrophysics · Physics 2009-10-31 Robert Braun , W. Butler Burton

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…

Astrophysics · Physics 2009-11-07 G. L. Hoffman , E. E. Salpeter , M. G. Pocceschi

We estimate the abundances of S and Fe in the high velocity cloud HVC 287.5+22.5+240, which has a velocity of +240 km/s with respect to the local standard of rest and is in the Galactic direction l~287, b~23. The measurements are based on…

A class of compact, isolated high-velocity clouds which plausibly represents a homogeneous subsample of the HVC phenomenon in a single physical state was objectively identified by Braun and Burton (1999). Six examples of the CHVCs,…

Astrophysics · Physics 2007-05-23 W. B. Burton , Robert Braun

A distinct sub-class of anomalous velocity HI emission features has emerged from recent high quality surveys of the Local Group environment, namely the compact high velocity clouds (CHVCs). A program of high-resolution imaging with the…

Astrophysics · Physics 2007-05-23 Robert Braun , W. Butler Burton