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相关论文: HIPASS High-Velocity Clouds: Properties of the Com…

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We consider here the class of compact, isolated, high-velocity HI clouds, CHVCs, which are sharply bounded in angular extent down to a limiting column density of 1.5x10^18 cm^-2. We describe our automated search algorithm and it's…

天体物理学 · 物理学 2007-05-23 W. B. Burton , R. Braun , V. de Heij

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…

天体物理学 · 物理学 2009-11-07 V. de Heij , R. Braun , W. B. Burton

We present a catalogue of high-velocity clouds (HVCs) from the Galactic All Sky Survey (GASS) of southern-sky neutral hydrogen, which has 57 mK sensitivity and 1 km/s velocity resolution and was obtained with the Parkes Telescope. Our…

We have identified a class of high-velocity clouds which are compact and apparently isolated. The clouds are compact in that they have angular sizes less than 2 degrees FWHM. They are isolated in that they are separated from neighboring…

天体物理学 · 物理学 2007-05-23 R. Braun , W. B. Burton

With the onset of the HI Parkes All-Sky Survey, a new view of the high-velocity cloud (HVC) distribution in the southern sky is being revealed. The dense spatial sampling and unbiased coverage of HIPASS gives it multiple advantages over…

天体物理学 · 物理学 2015-06-24 M. E. Putman , B. K Gibson

We present deep HI 21-cm and optical observations of the face-on spiral galaxy M 83 obtained as part of a project to search for high-velocity clouds (HVCs) in nearby galaxies. Anomalous-velocity neutral gas is detected toward M 83, with…

天体物理学 · 物理学 2011-02-11 Eric D. Miller , Joel N. Bregman , Bart P. Wakker

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,…

天体物理学 · 物理学 2007-05-23 W. B. Burton , Robert Braun

Six examples of the compact, isolated high-velocity HI clouds (CHVCs) identified by Braun and Burton (1999) have been imaged with the WSRT. The 65 confirmed objects in this class define a dynamically cold system, with a global minimum for…

天体物理学 · 物理学 2007-05-23 Robert Braun , Butler Burton

High-velocity clouds (HVCs) are neutral or ionised gas clouds in the vicinity of the Milky Way that are characterised by high radial velocities inconsistent with participation in the regular rotation of the Galactic disc. Previous attempts…

星系天体物理 · 物理学 2017-12-05 Tobias Westmeier

We describe an automated search through the Leiden/Dwingeloo HI Survey (LDS) for high-velocity clouds north of Dec=-28 deg. From the general catalog we extract a sample of isolated high-velocity clouds, CHVCs: anomalous-velocity HI clouds…

天体物理学 · 物理学 2009-11-07 V. de Heij , R. Braun , W. B. Burton

We suggest that the high--velocity clouds (HVCs) are large clouds, with typical diameters of 25 kpc and containing 5e7 solar masses of neutral gas and 3e8 solar masses of dark matter, falling onto the Local Group; altogether the HVCs…

天体物理学 · 物理学 2010-11-23 Leo Blitz , David N. Spergel , Peter J. Teuben , Dap Hartmann , W. Butler Burton

We present a catalog of 59 ultra-compact high velocity clouds (UCHVCs) extracted from the 40% complete ALFALFA HI-line survey. The ALFALFA UCHVCs have median flux densities of 1.34 Jy km/s, median angular diameters of 10', and median…

宇宙学与河外天体物理 · 物理学 2013-04-18 Elizabeth A. K. Adams , Riccardo Giovanelli , Martha P. Haynes

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…

天体物理学 · 物理学 2007-05-23 Robert Braun , W. Butler Burton

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…

天体物理学 · 物理学 2009-10-31 Robert Braun , W. Butler Burton

Searching the HI Parkes All-Sky Survey (HIPASS) and its northern extension, we detected a population of very compact high-velocity clouds (HVCs) with similar velocities in the Galactic standard-of-rest frame which appear to be arranged in…

天体物理学 · 物理学 2009-11-13 T. Westmeier , B. S. Koribalski

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…

天体物理学 · 物理学 2009-11-07 Philip R. Maloney , Mary E. Putman

We have imaged five compact high-velocity clouds in HI with arcmin angular- and km/s spectral-resolution using the WSRT. Supplementary total-power data, which is fully sensitive to both the cool and warm components of HI, is available for…

天体物理学 · 物理学 2009-11-07 V. de Heij , R. Braun , W. B. Burton

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…

星系天体物理 · 物理学 2015-05-30 M. E. Putman , D. R. Saul , E. Mets

We present a catalog of 1964 isolated, compact neutral hydrogen clouds from the Galactic Arecibo L-Band Feed Array Survey Data Release One (GALFA-HI DR1). The clouds were identified by a custom machine-vision algorithm utilizing Difference…

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…

天体物理学 · 物理学 2009-11-10 T. Westmeier , C. Bruens , J. Kerp
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