Number of results to display per page
Search Results
- ID:
- ivo://CDS.VizieR/J/ApJ/844/78
- Title:
- The high-redshift COBRA survey: IRAC obs.
- Short Name:
- J/ApJ/844/78
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present 190 galaxy cluster candidates (most at high redshift) based on galaxy overdensity measurements in the Spitzer/IRAC imaging of the fields surrounding 646 bent, double-lobed radio sources drawn from the Clusters Occupied by Bent Radio AGN (COBRA) Survey. The COBRA sources were chosen as objects in the Very Large Array FIRST survey that lack optical counterparts in the Sloan Digital Sky Survey to a limit of m_r_=22, making them likely to lie at high redshift. This is confirmed by our observations: the redshift distribution of COBRA sources with estimated redshifts peaks near z=1 and extends out to z~3. Cluster candidates were identified by comparing our target fields to a background field and searching for statistically significant (>=2{sigma}) excesses in the galaxy number counts surrounding the radio sources; 190 fields satisfy the >=2{sigma} limit. We find that 530 fields (82.0%) have a net positive excess of galaxies surrounding the radio source. Many of the fields with positive excesses but below the 2{sigma} cutoff are likely to be galaxy groups. Forty-one COBRA sources are quasars with known spectroscopic redshifts, which may be tracers of some of the most distant clusters known.
- ID:
- ivo://CDS.VizieR/J/ApJS/194/32
- Title:
- The HII Region Discovery Survey (HRDS). II.
- Short Name:
- J/ApJS/194/32
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Green Bank Telescope (GBT) HII Region Discovery Survey has doubled the number of known HII regions in the Galactic zone 343{deg}<=l<=67{deg} with |b|<=1{deg}. We detected 603 discrete hydrogen radio recombination line (RRL) components at 9GHz (3cm) from 448 targets. Our targets were selected based on spatially coincident mid-infrared and 20cm radio continuum emission. Such sources are almost invariably HII regions; we detected hydrogen RRL emission from 95% of our target sample. The sensitivity of the GBT and the power of its spectrometer together made this survey possible. Here, we provide a catalog of the measured properties of the RRL and continuum emission from the survey nebulae. The derived survey completeness limit, 180mJy at 9GHz, is sufficient to detect all HII regions ionized by single O-stars to a distance of 12kpc. We discovered 34 first quadrant negative-velocity HII regions, which lie at extreme distances from the Sun and appear to be part of the Outer Arm. We found RRL emission from 208 Spitzer GLIMPSE 8.0um "bubble" sources, 65 of which have been cataloged previously. It thus appears that nearly all GLIMPSE bubbles are HII regions and that ~50% of all Galactic HII regions have a bubble morphology at 8.0um.
- ID:
- ivo://CDS.VizieR/J/ApJ/864/40
- Title:
- The HIPASS Catalog (HICAT) + WISE galaxies
- Short Name:
- J/ApJ/864/40
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have measured the relationships between HI mass, stellar mass, and star formation rate using the HI Parkes All-Sky Survey Catalog (HICAT) and the Wide-field Infrared Survey Explorer (WISE). Of the 3513 HICAT sources, we find 3.4{mu}m counterparts for 2896 sources (80%), and provide new WISE-matched aperture photometry for these galaxies. For our principal sample of spiral galaxies with W1<=10mag and z<=0.01, we identify HI detections for 93% of the sample. We measure lower HI-stellar mass relationships for HI-selected samples that do not include spiral galaxies with little HI gas. Our observations of the spiral sample show that HI mass increases with stellar mass with a power-law index of 0.35; however, this value is dependent on T-type, which affects both the median and the dispersion of HI mass. We also observe an upper limit on the HI gas fraction, which is consistent with a halo spin parameter model. We measure the star formation efficiency of spiral galaxies to be constant at 10^-9.57^yr^-1^+/-0.4dex for 2.5 orders of magnitude in stellar mass, despite the higher stellar mass spiral showing evidence of quenched star formation.
- ID:
- ivo://anusf.anu.au/hipass
- Title:
- The HIPASS Project Data Archive
- Short Name:
- HIPASS
- Date:
- 23 Jan 2014 23:17:48
- Publisher:
- The Australian National University Supercomputer Facility
- Description:
- The HIPASS Project Data Archive. The acquisition of HI Parkes All Sky Survey (HIPASS) southern sky data commenced at the Australia Telescope National Facility's Parkes 64-m telescope in 1997 February, and was completed in 2000 March. HIPASS is the deepest HI survey yet of the sky south of declination +2°, and is sensitive to emission out to 170 h75-1 Mpc.
21786. The HI 4-PI Survey
- ID:
- ivo://nasa.heasarc/skyview/hi4pi
- Title:
- The HI 4-PI Survey
- Short Name:
- HI4PI
- Date:
- 09 May 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The HI 4-PI Survey (HI4PI) is a 21-cm all-sky survey of neutral atomic hydrogen. It is constructed from the Effelsberg-Bonn HI Survey (EBHIS), made with the 100-m radio telescope at Effelsberg/Germany, and the Galactic All-Sky Survey (GASS), observed with the Parkes 64-m dish in Australia. HI4PI comprises HI line emission from the Milky Way. This dataset is the atomic neutral hydrogen (HI) column density map derived from HI4PI (|Vlsr| < 600 km/s). Provenance: Argelander-Institut für Astronomie (AIfA), Max-Planck-Institut für Radioastronomie (MPIfR), and CSIRO/Australia; data provided by B. Winkel. This is a service of NASA HEASARC.
- ID:
- ivo://CDS.VizieR/I/239
- Title:
- The Hipparcos and Tycho Catalogues
- Short Name:
- I/239
- Date:
- 18 Nov 2021 11:08:10
- Publisher:
- CDS
- Description:
- The Hipparcos and Tycho Catalogues are the primary products of the European Space Agency's astrometric mission, Hipparcos. The satellite, which operated for four years, returned high quality scientific data from November 1989 to March 1993. Each of the catalogues contains a large quantity of very high quality astrometric and photometric data. In addition there are associated annexes featuring variability and double/multiple star data, and solar system astrometric and photometric measurements. In the case of the Hipparcos Catalogue, the principal parts are provided in both printed and machine-readable form (on CDROM). In the case of the Tycho Catalogue, results are provided in machine-readable form only (on CDROM). Although in general only the final reduced and calibrated astrometric and photometric data are provided, some auxiliary files containing results from intermediate stages of the data processing, of relevance for the more-specialised user, have also been retained for publication. (Some, but not all, data files are available from the Centre de Donnees astronomiques de Strasbourg.) The global data analysis tasks, proceeding from nearly 1000 Gbit of raw satellite data to the final catalogues, was a lengthy and complex process, and was undertaken by the NDAC and FAST Consortia, together responsible for the production of the Hipparcos Catalogue, and the Tycho Consortium, responsible for the production of the Tycho Catalogue. A fourth scientific consortium, the INCA Consortium, was responsible for the construction of the Hipparcos observing programme, compiling the best-available data for the selected stars before launch into the Hipparcos Input Catalogue. The production of the Hipparcos and Tycho Catalogues marks the formal end of the involvement in the mission by the European Space Agency and the four scientific consortia. For more complete and detailed information on the data, the user is advised to refer to Volume 1 ("Introduction and Guide to the Data", ESA SP-1200) of the printed Hipparcos and Tycho Catalogues. The user should also note that in order to convert the Double and Multiple Systems (Component solutions) data file hip_dm_c.dat into FITS format it is first necessary to filter the file according to whether the entry is a component record (identified by COMP in field DCM5) or a correlation record (identified by CORR in field DCM5) because of the different structures of the respective records. On a Unix system this can be achieved as follows: grep COMP hip_dm_c.dat > h_dm_com.dat grep CORR hip_dm_c.dat > h_dm_cor.dat The catalogue description file (this file) gives the relevant information for converting the main data files, including h_dm_cor.dat and h_dm_com.dat, into FITS format. The machine readable data files (i.e. those available on CD-ROM and the subset available from the CDS) contain several extra fields in addition to the data from the printed catalogue. These fields are identified by the letter `M' in the data label (e.g. the field DGM1 contains data only available in the machine readable file hip_dm_g.dat).
- ID:
- ivo://edu.euro-vo.org/extern/aladin_hi_shells
- Title:
- The HI shells of the Small Magellanic Cloud
- Date:
- 27 Dec 2024 08:31:12
- Publisher:
- The GAVO DC team
- Description:
- This tutorial employs the Aladin VO client to explore neutral hydrogen shells around the SMC; it demonstrates using image servers, catalog servers, and advanced overplotting within Aladin.
21789. The HIZOA-S survey
- ID:
- ivo://CDS.VizieR/J/AJ/151/52
- Title:
- The HIZOA-S survey
- Short Name:
- J/AJ/151/52
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A blind HI survey of the extragalactic sky behind the southern Milky Way has been conducted with the multibeam receiver on the 64m Parkes radio telescope. The survey covers the Galactic longitude range 212{deg}<l<36{deg} and Galactic latitudes |b|<5{deg} to an rms sensitivity of 6mJy per beam per 27km/s channel and yields 883 galaxies to a recessional velocity of 12000km/s. The survey covers the sky within the HI Parkes All-Sky Survey (HIPASS) area to greater sensitivity, finding lower HI mass galaxies at all distances, and probing more completely the large-scale structures at and beyond the distance of the Great Attractor. Fifty-one percent of the HI detections have an optical/near-infrared (NIR) counterpart in the literature. A further 27% have new counterparts found in existing, or newly obtained, optical/NIR images. The counterpart rate drops in regions of high foreground stellar crowding and extinction, and for low HI mass objects. Only 8% of all counterparts have a previous optical redshift measurement. The HI sources are found independently of Galactic extinction, although the detection rate drops in regions of high Galactic continuum. The survey is incomplete below a flux integral of approximately 3.1Jy/km/s and mean flux density of approximately 21mJy, with 75% and 81% of galaxies being above these limits, respectively. Taking into account dependence on both flux and velocity width, and constructing a scaled dependence on the flux integral limit with velocity width (w^0.74^), completeness limits of 2.8Jy/km/s and 17mJy are determined, with 92% of sources above these limits. A notable new galaxy is HIZOA J1353-58, a possible companion to the Circinus galaxy. Merging this catalog with the similarly conducted northern extension, large-scale structures are delineated, including those within the Puppis and Great Attractor regions and the Local Void. Several newly identified structures are revealed here for the first time. Three new galaxy concentrations (NW1, NW2, and NW3) are key in confirming the diagonal crossing of the Great Attractor Wall between the Norma Cluster and the CIZA J1324.7-5736 cluster. Further contributors to the general mass overdensity in that area are two new clusters (CW1 and CW2) in the nearer Centaurus Wall, one of which forms part of the striking 180{deg} (100h^-1^Mpc) long filament that dominates the southern sky at velocities of ~3000 km/s, and the suggestion of a further wall at the Great Attractor distance at slightly higher longitudes.
- ID:
- ivo://CDS.VizieR/VI/103
- Title:
- The Hopkins Ultraviolet Telescope (HUT)
- Short Name:
- VI/103
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Hopkins Ultraviolet Telescope HUT was one of three ultraviolet instruments of the ASTRO-1 mission flown on the space shuttle Columbia during 2-10 December 1990. 106 spectrophotometric observations of 77 targets were obtained in the far-UV (i.e., 912-1850{AA}) at a resolution of ~3{AA}. A few sources were observed in the 415-912{AA} region with a 1.5{AA} resolution. The same three instruments were later flown on the space shuttle Endeavour from 3-17 March 1995 as part of the ASTRO-2 mission. During the longer ASTRO-2 mission, 385 observations of 265 targets were obtained.
