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Related papers: The GALFA-HI Compact Cloud Catalog

200 papers

The Arecibo Galaxy Environment Survey (AGES) has detected a nearby HI source at a heliocentric velocity of +363 km/s . The object was detected through its neutral hydrogen emission and has an obvious possible optical counterpart in Sloan…

Astrophysics of Galaxies · Physics 2015-06-19 R. Taylor , R. F. Minchin , H. Herbst , R. Smith

We present deep HI observations of three compact high-velocity clouds (CHVCs). The main goal is to study their diffuse warm gas and compact cold cores. We use both low- and high-resolution data obtained with the 100 m Effelsberg telescope…

Astrophysics of Galaxies · Physics 2015-06-18 Shahram Faridani , Lars Flöer , Jürgen Kerp , Tobias Westmeier

We present results from an optical search for Local Group dwarf galaxy candidates associated with the Ultra-Compact High Velocity Clouds (UCHVCs) discovered by the ALFALFA neutral hydrogen survey. The ALFALFA UCHVCs are isolated, compact HI…

The Arecibo Legacy Fast ALFA survey is in the process of yielding a complete HI dataset of the Virgo Cluster and its environs (Giovanelli et al. 2007, Kent et al., in preparation). Assuming a distance to Virgo of 16.7 Mpc, the minimum…

Astrophysics · Physics 2009-11-13 Brian R. Kent

We investigate the hypothesis that compact high-velocity clouds (CHVC) are the "missing" dwarf galaxies of the Local Group, by searching them for populations of resolved stars. To this end we conducted two distinct tests based on optical…

Astrophysics · Physics 2011-08-23 U. Hopp , R. E. Schulte-Ladbeck , J. Kerp

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…

Astrophysics · Physics 2007-05-23 M. E. Putman

We have mapped 11 compact high-velocity clouds (CHVCs) in the 21-cm line emission of neutral, atomic hydrogen, using the Effelsberg 100-m radio telescope. The aim of our observations was to study the overall distribution of the warm neutral…

Astrophysics · Physics 2009-11-10 T. Westmeier , C. Bruens , J. Kerp

In this study, we present an update of a compilation of line width measurements of neutral atomic hydrogen (HI) galaxy spectra at 21 cm wavelength. Our All Digital HI (ADHI) catalog consists of the previous release augmented with our new HI…

Cosmology and Nongalactic Astrophysics · Physics 2021-02-17 A. Dupuy , H. M. Courtois , D. Guinet , R. B. Tully , E. Kourkchi

We have taken advantage of the improved baselines and higher sensitivity available with the upgraded Arecibo 305m telescope to create a new HI spectral line catalog of disk galaxies which can be used as a reference catalog for anyone…

Astrophysics · Physics 2008-11-26 K. O'Neil

The halo of our Galaxy is populated with a significant number of high-velocity clouds (HVCs) moving with a speed up to $500$ km/s. It is suggested that these HVCs might contain a non-negligible fraction of the missing baryons. The main aim…

Astrophysics of Galaxies · Physics 2024-12-03 Noraiz Tahir , Martin Lopez Corredoira , Francesco De Paolis

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…

Astrophysics of Galaxies · Physics 2024-10-21 Scott Lucchini , Jiwon Jesse Han , Lars Hernquist , Charlie Conroy

We present ultraviolet (UV) follow-up of a sample of potential dwarf galaxy candidates selected for their neutral hydrogen (HI) properties, taking advantage of the low UV background seen by the GALEX satellite and its large and publicly…

Astrophysics of Galaxies · Physics 2015-08-06 Jennifer Donovan Meyer , J. E. G. Peek , Mary Putman , Jana Grcevich

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

We present an all-sky catalog of 869 nearby galaxies, having individual distance estimates within 11 Mpc or corrected radial velocities V_{LG} < 600 km/s. The catalog is a renewed and expanded version of the "Catalog of Neighboring…

Cosmology and Nongalactic Astrophysics · Physics 2013-03-25 Igor D. Karachentsev , Dmitry I. Makarov , Elena I. Kaisina

New 21cm observations with the Green Bank Telescope show that a significant fraction of the HI in the inner Galaxy's halo 1 kpc from the midplane exists in the form of discrete clouds. Some look very much like a Spitzer ``standard'' diffuse…

Astrophysics · Physics 2007-05-23 Felix J. Lockman

We identify 814 discrete HI clouds in 40 dwarf irregular galaxies from the LITTLE THINGS survey using an automated cloud-finding algorithm. The cloud masses range from ~10^3 to 10^7 Msolar, have a surface density averaged over all of the…

Astrophysics of Galaxies · Physics 2019-06-05 Deidre A. Hunter , Bruce G. Elmegreen , Clara L. Berger

We present a census of neutral gas in the Milky Way disk and halo down to limiting column densities of $N$(HI)$\sim10^{14}$ cm$^{-2}$ using measurements of HI Lyman-series absorption from the Far Ultraviolet Spectroscopic Explorer (FUSE).…

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

We combine data from the Sloan Digital Sky Survey (SDSS) and the Arecibo Legacy Fast ALFA Survey (ALFALFA) to study the cold atomic gas content of galaxies in groups and clusters in local universe. A careful cross-matching of galaxies in…

Astrophysics of Galaxies · Physics 2015-10-14 Ilsang Yoon , Jessica L. Rosenberg

We study the hypothesis that high-velocity clouds (HVCs) may originate from instabilities within the gaseous phase of the Galactic halo. According to the hydrostatic equilibrium model of Kalberla & Kerp (1998), we determine the probability…

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