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- ID:
- ivo://CDS.VizieR/J/A+A/406/829
- Title:
- Background galaxies in the WSRT wide-field Survey
- Short Name:
- J/A+A/406/829
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have used the Westerbork array to carry out an unbiased wide-field survey for H I emission features, achieving an RMS sensitivity of about 18mJy/beam at a velocity resolution of 17km/s over 1800deg2 and between -1000<VHel<+6500 km/s. The primary data consists of auto-correlation spectra with an effective angular resolution of 49' FWHM. The survey region is centered approximately on the position of Messier 31 and is Nyquist-sampled over 60x30 deg in RAxDec. In this paper we present the results for our HI detections of external galaxies at positive Local Group Standard of Rest (LGSR) velocity. We detect 155 external galaxies in excess of 8 sigma in integrated HI flux density. Plausible optical associations are found within a 30' search radius for all but one of our HI detections in DSS images, although several are not previously catalogued or do not have published redshift determinations. Our detection without a DSS association is at low galactic latitude. Twenty-three of our objects are detected in HI for the first time. We classify almost half of our detections as "confused", since one or more companions is catalogued within a radius of 30' and a velocity interval of 400km/s. Nine of the detected galaxies fall so near the edges of the survey coverage (either spatially or in velocity) that their parameters can not be reliably determined. These nine objects are excluded from the enclosed table.
- ID:
- ivo://CDS.VizieR/J/ApJS/79/77
- Title:
- Bell Lab. H I Survey - High Velocity Clouds
- Short Name:
- J/ApJS/79/77
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The sky north of declination -40 deg. was observed in the 21 cm line of atomic hydrogen with the FWHM = 2 deg. beam of the 20 foot horn reflector at AT&T Bell Laboratories, Crawford Hill. The survey covers a velocity range of 654 km/s centered on the Galactic standard of rest, with 5.3 km/s wide filters. This survey is distinguished by its sensitivity to low surface brightness features (antenna temperature about 50 mK) and relative freedom from sidelobe contamination. The high-velocity cloud list was extracted and catalogued automatically from the survey data.
- ID:
- ivo://CDS.VizieR/VIII/10
- Title:
- Bell Laboratories H I Profiles
- Short Name:
- VIII/10
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This survey consists of H I 21-cm spectra covering galactic latitudes |b|>10degrees, North of Declination -40deg, observed with the 20-foot horn reflector at AT&T Bell Laboratories, Crawford Hill. The instrument beam is 2{deg} (FWHM). The data consist of 124-channel profiles sorted in Galactic latitude and longitude; each channel has a width of 5.3km/s. The data were obtained by holding the telescope fixed and letting the sky drift through. Then the natural coordinate system for the data is in equatorial coordinates, so the data are not gridded in Galactic coordinates. Note that this catalog represents the Bell Laboratories H I Survey in a preliminary version; it is superseded by Catalog VIII/28.
- ID:
- ivo://CDS.VizieR/J/AJ/148/75
- Title:
- Bent-tailed radio galaxies Chandra Deep Field South
- Short Name:
- J/AJ/148/75
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Using the 1.4GHz Australia Telescope Large Area Survey, supplemented by the 1.4GHz Very Large Array images, we undertook a search for bent-tailed (BT) radio galaxies in the Chandra Deep Field South. Here we present a catalog of 56 detections, which include 45 BT sources, 4 diffuse low-surface-brightness objects (1 relic, 2 halos, and 1 unclassified object), and a further 7 complex, multi-component sources. We report BT sources with rest-frame powers in the range 10^22^<=P_1.4 GHz_<=10^26^W/Hz, with redshifts up to 2 and linear extents from tens of kiloparsecs up to about 1Mpc. This is the first systematic study of such sources down to such low powers and high redshifts and demonstrates the complementary nature of searches in deep, limited area surveys as compared to shallower, large surveys. Of the sources presented here, one is the most distant BT source yet detected at a redshift of 2.1688. Two of the sources are found to be associated with known clusters: a wide-angle tail source in A3141 and a putative radio relic which appears at the infall region between the galaxy group MZ 00108 and the galaxy cluster AMPCC 40. Further observations are required to confirm the relic detection, which, if successful, would demonstrate this to be the least powerful relic yet seen with P_1.4GHz_=9x10^22^W/Hz. Using these data, we predict future 1.4GHz all-sky surveys with a resolution of ~10 arcsec and a sensitivity of 10{mu}Jy will detect of the order of 560,000 extended low-surface-brightness radio sources of which 440,000 will have a BT morphology.
- ID:
- ivo://CDS.VizieR/VIII/11
- Title:
- Berkeley Low-Latitude H I Survey
- Short Name:
- VIII/11
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This survey consists of H I 21-cm spectra covering galactic latitudes from -10 degrees to +10 degrees and galactic longitudes from 10degrees to 250degrees. The observations were made with the Hat Creek 85-foot telescope between 1968 and 1970. The individual spectra contain 238 points per profile spaced every 5kHz and cover a velocity range of 250km/s. The velocity resolution is 2km/s (half-power of each filter) and the half-power beamwidth is 35arcmin. The spacing between points observed on the sky are 0.25degrees in galactic latitude and 0.5degrees in galactic longitude. Each spectrum or record consists of a header followed by 238 antenna temperatures. The header contains the galactic longitude, galactic latitude, and central velocity (LSR). The catalog contains a total of 38961 spectra.
- ID:
- ivo://CDS.VizieR/J/AJ/124/1954
- Title:
- 1000 brightest HIPASS galaxies catalog
- Short Name:
- J/AJ/124/1954
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The HI Parkes All-Sky Survey (HIPASS) is a blind 21cm survey for extragalactic neutral hydrogen, covering the whole southern sky. The HIPASS Bright Galaxy Catalog (BGC) is a subset of HIPASS and contains the 1000 HI brightest (peak flux density) galaxies. Here we present the 138 HIPASS BGC galaxies that had no redshift measured prior to the Parkes multibeam HI surveys. Of the 138 galaxies, 87 are newly catalogued. Newly catalogued is defined as having no optical (or infrared) counterpart in the NASA/IPAC Extragalactic Database. Using the Digitized Sky Survey, we identify optical counterparts for almost half of the newly catalogued galaxies, which are typically of irregular or Magellanic morphological type. Several HI sources appear to be associated with compact groups or pairs of galaxies rather than an individual galaxy. The majority (57) of the newly catalogued galaxies lie within 10{deg} of the Galactic plane and are missing from optical surveys as a result of confusion with stars or dust extinction. This sample also includes newly catalogued galaxies first discovered by Henning et al. in the HI shallow survey of the zone of avoidance. The other 30 newly catalogued galaxies escaped detection because of their low surface brightness or optical compactness. Only one of these, HIPASS J0546-68, has no obvious optical counterpart, as it is obscured by the Large Magellanic Cloud. We find that the newly catalogued galaxies with |b|>10{deg} are generally lower in HI mass and narrower in velocity width compared with the total HIPASS BGC. In contrast, newly catalogued galaxies behind the Milky Way are found to be statistically similar to the entire HIPASS BGC. In addition to these galaxies, the HIPASS BGC contains four previously unknown HI clouds. Description:
- ID:
- ivo://CDS.VizieR/J/ApJ/710/613
- Title:
- Broad HI absorbers
- Short Name:
- J/ApJ/710/613
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We compile a catalog of reliable BLA (thermally broadened Ly{alpha} absorber) candidates along seven active galactic nucleus sight lines from a larger set of Ly{alpha} absorbers observed by the Space Telescope Imaging Spectrograph on the Hubble Space Telescope (HST). We compare our measurements based on independent reduction and analysis of the data to those published by other research groups. We examine the detailed structure of each absorber and determine a reliable line width and column density. Purported BLAs are grouped into probable (15), possible (48), and non-BLA (56) categories. Based on 164 measured curve of growth (COG) HI line measurements, we statistically correct the observed line widths via a Monte Carlo simulation. Finally, we present new, high signal-to-noise ratio observations of several of the BLA candidate lines from Early Release Observations made by the Cosmic Origins Spectrograph on HST.
- ID:
- ivo://CDS.VizieR/J/A+A/647/A63
- Title:
- 4C52.37 and 3C 293 parsec-scale HI outflows
- Short Name:
- J/A+A/647/A63
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Massive outflows of neutral atomic hydrogen (HI) have been observed in absorption in a number of radio galaxies and are considered a signature of active galactic nucleus (AGN) feedback. These outflows on kiloparsec scales have not been investigated in great detail as they require high-angular-resolution observations to be spatially resolved. In some radio AGN, they are likely to be the result of the radio jets interacting with the interstellar medium. We have used the global very-long-baseline-interferometry (VLBI) array to map the HI outflow in a small sample of young and restarted radio galaxies that we previously observed with the Very Large Array (VLA) and the Westerbork Synthesis Radio Telescope (WSRT) at a lower resolution. Here we report on our findings for 4C 52.37 and 3C 293 and we discuss the sample including the previously published 4C 12.50 and 3C 236. For 4C 52.37, we present the first ever HI VLBI observations, which recovered the majority of the outflowing HI gas in the form of clouds toward the central 100pc of the AGN. The clouds are blueshifted by up to ~600km/s with respect to the systemic velocity. 3C 293 is largely resolved out in our VLBI observation, but toward the VLBI core we detect some outflowing HI gas blueshifted with respect to the systemic velocity by up to ~300km/s. We also find indications of outflowing gas toward the other parts of the western lobe suggesting that the HI outflow is extended. Overall, we find that the fraction of HI gas recovered by our VLBI observations varies significantly within our sample, ranging from complete (4C 12.50) to marginal (3C 293). However, in all cases we find evidence for a clumpy structure of both the outflowing and the quiescent gas, consistent with predictions from numerical simulations. All the outflows include at least a component of relatively compact clouds with masses in the range of 10^4^-10^5^M_{sun}_. The outflowing clouds are often already observed at a few tens of parsecs (in projection) from the core. We find indications that the HI outflow might have a diffuse component, especially in larger sources. Our results support the interpretation that we observe these AGNs at different stages in the evolution of the interaction between the jet and the interstellar medium and this is reflected in the properties of the outflowing gas as predicted by numerical simulations.
- ID:
- ivo://CDS.VizieR/J/ApJS/171/419
- Title:
- Catalog of LMC HI clouds
- Short Name:
- J/ApJS/171/419
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- 21cm neutral hydrogen interferometric survey of the Large Magellanic Cloud (LMC) combined with the Parkes multibeam HI single-dish survey (2003MNRAS.339...87S) clearly shows that the HI gas is distributed in the form of clumps or clouds. The HI clouds and clumps have been identified using a thresholding method with three separate brightness temperature thresholds (T_b_). Each catalog of HI cloud candidates shows a power-law relationship between the sizes and the velocity dispersions of the clouds roughly following the Larson law scaling {sigma}_v_{prop.to}R^0.5^, with steeper indices associated with dynamically hot regions. The clouds in each catalog have roughly constant virial parameters as a function of mass, suggesting that the clouds are all in roughly the same dynamical state, but the values of the virial parameter are significantly larger than unity, showing that turbulent motions dominate gravity in these clouds. The mass distribution of the clouds is a power law with differential indices between -1.6 and -2.0 for the three catalogs. In contrast, the distribution of mean surface densities is a lognormal distribution.
