English
Related papers

Related papers: High-Velocity Clouds in M 83 and M 51

200 papers

In this contribution the current state of knowledge about the high-velocity clouds (HVCs) is summarized. Recent progress has shown that the HVCs are a diverse phenomenon. The intermediate-velocity clouds (IVCs) are likely to be part of a…

Astrophysics · Physics 2007-05-23 B. P. Wakker

The high-velocity cloud (HVC) Complex A is a probe of the physical conditions in the Galactic halo. The kinematics, morphology, distance, and metallicity of Complex A indicate that it represents new material that is accreting onto the…

Astrophysics of Galaxies · Physics 2013-08-06 Kathleen A. Barger , Lawrence M. Haffner , Bart P. Wakker , Alex S. Hill , Greg J. Madsen , Allison K. Duncan

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

Ongoing accretion onto galactic disks has been recently theorized to progress via the unstable cooling of the baryonic halo into condensed clouds. These clouds have been identified as analogous to the High-Velocity Clouds (HVCs) observed in…

Astrophysics · Physics 2009-11-13 J. E. G. Peek , M. E. Putman , Jesper Sommer-Larsen

In this paper, we limit the stellar content of 13 high-velocity clouds (HVCs; including 1 compact HVC) using the detection limits of a new survey for resolved Milky Way satellite galaxies in the Sloan Digital Sky Survey Early Data Release…

High-velocity clouds (HVCs) in the Galactic center have garnered significant attention due to their mysterious formation, potentially linked to starburst events or supermassive black hole activity in the region. However, it remains…

Astrophysics of Galaxies · Physics 2025-02-25 Mengfei Zhang , Miao Li , Peixin Zhu

A recent discovery of two stellar clusters associated with the diffuse high-latitude cloud HRK 81.4-77.8 has important implications for star formation in the Galactic halo. We derive a plausible distance estimate to HRK 81.4-77.8 primarily…

Astrophysics of Galaxies · Physics 2016-05-04 J. Kerp , D. Lenz , T. Roehser

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

Optical emission lines provide an important new window on the HVCs. Recent studies of the H-alpha line reveal that ionized gas is pervasively associated with the neutral hydrogen in HVCs. The Wisconsin H-Alpha Mapper (WHAM) instrument has…

Astrophysics · Physics 2007-05-23 S. L. Tufte , R. J. Reynolds , L. M. Haffner

Very sensitive 21cm HI measurements have been made at several locations around the Local Group galaxy M31 using the Green Bank Telescope (GBT) at an angular resolution of 9.1', with a 5$\sigma$ detection level of $\rm{N_{HI} = 3.9 \times…

Astrophysics of Galaxies · Physics 2016-01-27 Spencer A. Wolfe , Felix J. Lockman , D. J. Pisano

Using observed GALEX far-ultraviolet (FUV) fluxes and VLA images of the 21-cm HI column densities, along with estimates of the local dust abundances, we measure the volume densities of a sample of actively star-forming giant molecular…

Astrophysics · Physics 2009-11-13 Jonathan S. Heiner , Ronald J. Allen , O. Ivy Wong , Pieter C. van der Kruit

Hypervelocity stars (HVSs) travel from the Galactic Centre across the dark matter halo of the Milky Way, where they are observed with velocities in excess of the Galactic escape speed. Because of their quasi-radial trajectories, they…

Astrophysics of Galaxies · Physics 2019-06-14 O. Contigiani , E. M. Rossi , T. Marchetti

Understanding the distribution of gas in and around galaxies is vital for our interpretation of galaxy formation and evolution. As part of the Arecibo Galaxy Environment Survey (AGES) we have observed the neutral hydrogen (HI) gas in and…

Astrophysics of Galaxies · Physics 2017-03-29 Olivia Keenan , Jonathan Davies , Rhys Taylor , Robert Minchin

We present HI observations of the compact high-velocity cloud HVC289+33+251 that was discovered by Putman et al. (2002). Observations with the 100-m Effelsberg telescope demonstrate that this cloud is still unresolved by the 9' beam of the…

Astrophysics · Physics 2011-08-23 C. Bruens , T. Westmeier

We report a new search for 12CO(1-0) emission in high-velocity clouds (HVCs) performed with the IRAM 30 m telescope. This search was motivated by the recent detection of cold dust emission in the HVCs of Complex C. Despite a spatial…

Astrophysics · Physics 2009-11-13 M. Dessauges-Zavadsky , F. Combes , D. Pfenniger

We have observed the NGC 2403 group of galaxies using the Robert C. Byrd Green Bank Telescope (GBT) in a search for faint, extended neutral hydrogen clouds similar to the clouds found around the M81/M82 group, which is located approximately…

Astrophysics of Galaxies · Physics 2015-05-13 Katie M. Chynoweth , Glen I. Langston , Kelly Holley-Bockelmann , Felix J. Lockman

Spiral galaxies are surrounded by a widely distributed hot coronal gas and seem to be fed by infalling clouds of neutral hydrogen gas with low metallicity and high velocities. We numerically study plasma waves produced by the collisions of…

Astrophysics of Galaxies · Physics 2011-03-08 Petr Jelinek , Gerhard Hensler

We have used moderate-resolution (FWHM ~ 25 km/sec) spectra of AGNs and QSOs observed by the Far Ultraviolet Spectroscopic Explorer (FUSE) to make the first definitive measurements of absorption by hot gas in high velocity clouds (HVCs) at…

We report the discovery of molecular hydrogen absorption in a Galactic high-velocity cloud (HVC) in the direction of the Large Magellanic Cloud. For the same HVC we derive an iron abundance which is half of the solar value. Thus, all…

Astrophysics · Physics 2009-10-31 P. Richter , K. S. de Boer , H. Widmann , N. Kappelmann , W. Gringel , M. Grewing , J. Barnstedt

(ABRIDGED) Gaseous halos of nine nearby galaxies (with redshifts cz < 6000 km/s) were probed at large galactocentric radii using background quasars observed with HST GHRS and STIS. The projected quasar-galaxy separations range from 55 to…

Astrophysics · Physics 2014-10-13 Stephanie Cote , Rosemary Wyse , Claude Carignan , Ken Freeman , Tom Broadhurst
‹ Prev 1 3 4 5 6 7 10 Next ›