English
Related papers

Related papers: Summary of Recent Progress in Understanding HVCs

200 papers

We present hydrodynamic simulations of high-velocity clouds (HVCs) traveling through the hot, tenuous medium in the Galactic halo. A suite of models was created using the FLASH hydrodynamics code, sampling various cloud sizes, densities,…

Astrophysics of Galaxies · Physics 2015-05-28 Kyujin Kwak , David B. Henley , Robin L. Shelton

We report an accurate distance of d = 10+/-2.5kpc to the high-velocity cloud Complex C. Using high signal-to-noise Keck/HIRES spectra of two horizontal-branch stars, we have detected CaII K absorption lines from the cloud. Significant…

Astrophysics · Physics 2009-11-13 C. Thom , J. E. G. Peek , M. E. Putman , Carl Heiles , K. M. G. Peek , R. Wilhelm

This study developed an automated identification procedure for compact clouds with broad velocity widths in the spectral line data cubes of highly crowded regions. The procedure was applied to the CO J=3-2 line data, obtained using the…

Astrophysics of Galaxies · Physics 2022-09-27 Tomoharu Oka , Asaka Uruno , Rei Enokiya , Taichi Nakamura , Yuto Yamasaki , Yuto Watanabe , Sekito Tokuyama , Yuhei Iwata

We present a geometrodynamical method for determining distances to orbital streams of HI gas in the Galaxy. The method makes use of our offset from the Galactic centre and assumes that the gas comprising the stream nearly follows a planar…

Astrophysics · Physics 2009-11-13 Shoko Jin , Donald Lynden-Bell

The Arecibo HI Strip Survey probed the halos of ~300 cataloged galaxies and the environments of ~14 groups with sensitivity to neutral hydrogen masses > 10^7 M_sun. The survey detected no objects with properties resembling the High Velocity…

Astrophysics · Physics 2009-10-31 M. A. Zwaan , F. H. Briggs

The VLA Galactic Plane Survey (VGPS) of the first Galactic quadrant was searched for HI emission with velocities well above the maximum velocity allowed by Galactic rotation. A sample of 17 small fast-moving clouds was identified. The…

To gain insight into four highly ionized high-velocity clouds (HVCs) discovered by Sembach et al. (1999), we have analyzed data from the Hubble Space Telescope (HST) and Far Ultraviolet Spectroscopic Explorer (FUSE) for the PKS 2155-304 and…

Astrophysics · Physics 2009-11-10 J. A. Collins , J. M. Shull , M. L. Giroux

We have determined column densities of H I and/or H_2 for sight lines in the Magellanic Clouds from archival HST and FUSE spectra of H I Lyman-alpha and H_2 Lyman-band absorption. Together with some similar data from the literature, we now…

Astrophysics of Galaxies · Physics 2015-06-03 Daniel E. Welty , Rui Xue , Tony Wong

The distance to the Large Magellanic Cloud (LMC) has long been of key importance for the distance ladder and the distances to all galaxies, and as such many groups have provided measurements of its distance modulus (\mu) with many methods…

Astrophysics · Physics 2009-06-23 Bradley E. Schaefer

The vertical velocity in convective clouds ($w_c$) mediates convective anvil development and global moisture transport, influencing Earth's energy budget, but has yet to be estimated globally over long periods due to the absence of…

Atmospheric and Oceanic Physics · Physics 2026-04-07 Amel Derras-Chouk , Gregory Elsaesser , Zhengzhao Johnny Luo , Toshi Matsui , Andreas F. Prein , Jingbo Wu

We report that neutral hydrogen (HI) gas clouds, resembling High Velocity Clouds (HVCs) observed in the Milky Way (MW), appear in MW-sized disk galaxies formed in high-resolution Lambda Cold Dark Matter (LCDM) cosmological simulations which…

Astrophysics · Physics 2007-05-23 Tim W. Connors , Daisuke Kawata , Jeremy Bailin , Jason Tumlinson , Brad K. Gibson

We present high resolution (R = 60,000) measurements of the NaI D1 and D2 (5890 A) and CaII K (3933 A) interstellar absorption line profiles recorded towards several post-AGB stars located within the M13 and M15 globular clusters,…

Astrophysics of Galaxies · Physics 2015-05-13 B. Y. Welsh , J. M. Wheatley , R. Lallement

HI 21-cm absorption lines are investigated to determine the origin of the neutral atomic hydrogen (HI) of the Magellanic Bridge (MB). Using the MeerKat Absorption Line Survey (MALS) data we report the detection of an HI absorption line at a…

Astrophysics of Galaxies · Physics 2025-10-22 A. P. M. Morelli , J. Kerp , N. Gupta , F. Combes , S. A. Balashev , P. Noterdaeme , H. Chen , K. L. Emig , E. Momjian

We combine the catalogs of compact high-velocity HI clouds extracted from the LDS and HIPASS surveys and analyze the all-sky properties of the ensemble. Five principal observables are defined for the CHVC population: (1) the spatial…

Astrophysics · Physics 2009-11-07 V. de Heij , R. Braun , W. B. Burton

Ongoing accretion of low-metallicity gas onto the disk is a natural prediction of semi-analytical Galactic chemical evolution models. This star formation fuel ameliorates the overproduction of metal-poor G- and K-dwarfs in the solar…

Astrophysics · Physics 2007-05-23 Brad K. Gibson

The LMC, SMC, and the Milky Way are a spectacular set of interacting galaxies. The prominent tidal arms which protrude from the Magellanic Clouds extend for tens of kiloparsecs and cover a large part of the southern sky. These arms, and the…

Astrophysics · Physics 2007-05-23 C. Bruens , J. Kerp , L. Staveley-Smith

A recent paper by Stanimirovic etal (2008) presents quit interesting results from HI observations of the Magellanic Stream (MS) tip. The high spatial resolution of the data reveals rich and complex morphological and kinematic structures;…

Astrophysics · Physics 2008-09-29 Itzhak Goldman

Thanks to the outstanding capabilites of the HST, our current knowledge about the M31 globular clusters (GCs) is similar to our knowledge of the Milky Way GCs in the 1960s-1970s, which set the basis for studying the halo and galaxy…

Astrophysics of Galaxies · Physics 2015-06-05 Luciana Federici , Carla Cacciari , Michele Bellazzini , Flavio Fusi Pecci , Silvia Galleti , Sibilla Perina

High-velocity atomic clouds in the Galactic center have attracted significant attention due to their enigmatic formation process, which is potentially linked to the starburst or supermassive black hole activities in the region. Further, the…

Astrophysics of Galaxies · Physics 2023-12-27 Mengfei Zhang , Miao Li

There has been much debate in recent decades as to what fraction of ionizing photons from star forming regions in the Galactic disk escape into the halo. The recent detection of the Magellanic Stream in optical line emission at the CTIO 4m…

Astrophysics · Physics 2007-05-23 J. Bland-Hawthorn , P. R. Maloney