- ID:
- ivo://CDS.VizieR/J/MNRAS/329/877
- Title:
- The CLASS blazar survey. II.
- Short Name:
- J/MNRAS/329/877
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper presents the optical properties of the objects selected in the CLASS blazar survey. Because an optical spectrum is now available for 70 per cent of the 325 sources present in the sample, a spectral classification, based on the appearance of the emission/absorption lines, is possible. A wide variety of optical spectral types is found. Besides `classical' BL Lacs (42), BL Lac candidates (5) and high-power (P_5GHz_>10^26^W/Hz) flat spectrum radio quasars (67), a significant number of `passive' elliptical galaxies (41) is also found. Moreover, 33 broad emission line objects with a low radio power (P(5GHz)>10^26^W/Hz) are discovered, suggesting that at least a fraction (~24-30 per cent) of low-power blazars have a broad line region. Finally, 34 objects showing only narrow emission lines, either as a result of some starburst activity in the host galaxy or as a result of the presence of an active galactic nucleus, appear in the sample.
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Search Results
- ID:
- ivo://CDS.VizieR/J/MNRAS/430/2464
- Title:
- The CLASS BL Lac sample
- Short Name:
- J/MNRAS/430/2464
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper presents a new sample of BL Lac objects selected from a deep (30mJy) radio survey of flat spectrum radio sources (the CLASS blazar survey). The sample is one of the largest well-defined samples in the low-power regime with a total of 130 sources of which 55 satisfy the 'classical' optical BL Lac selection criteria, and the rest have indistinguishable radio properties. The primary goal of this study is to establish the radio luminosity function (RLF) on firm statistical ground at low radio luminosities where previous samples have not been able to investigate. The gain of taking a peek at lower powers is the possibility to search for the flattening of the luminosity function which is a feature predicted by the beaming model but which has remained elusive to observational confirmation. In this study, we extend for the first time the BL Lac RLF down to very low radio powers ~10^22^W/Hz, i.e. two orders of magnitude below the RLF currently available in the literature. In the process, we confirm the importance of adopting a broader, and more physically meaningful set of classification criteria to avoid the systematic missing of low-luminosity BL Lacs. Thanks to the good statistics we confirm the existence of weak but significant positive cosmological evolution for the BL Lac population, and we detect, for the first time the flattening of the RLF at L~10^25^W/Hz in agreement with the predictions of the beaming model.
- ID:
- ivo://CDS.VizieR/VII/250
- Title:
- The 2dF Galaxy Redshift Survey (2dFGRS)
- Short Name:
- VII/250
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The 2dF Galaxy Redshift Survey (2dFGRS) is a major spectroscopic survey taking full advantage of the unique capabilities of the 2dF facility built by the Anglo-Australian Observatory. The 2dFGRS is integrated with the 2dF QSO survey (2QZ, Cat. VII/241). The 2dFGRS obtained spectra for 245591 objects, mainly galaxies, brighter than a nominal extinction-corrected magnitude limit of b_J_=19.45. Reliable (quality>=3) redshifts were obtained for 221414 galaxies. The galaxies cover an area of approximately 1500 square degrees selected from the extended APM Galaxy Survey in three regions: a North Galactic Pole (NGP) strip, a South Galactic Pole (SGP) strip, and random fields scattered around the SGP strip. Redshifts are measured from spectra covering 3600-8000 Angstroms at a two-pixel resolution of 9.0 Angstrom and a median S/N of 13 per pixel. All redshift identifications are visually checked and assigned a quality parameter Q in the range 1-5; Q>=3 redshifts are 98.4% reliable and have an rms uncertainty of 85 km/s. The overall redshift completeness for Q>=3 redshifts is 91.8% but this varies with magnitude from 99% for the brightest galaxies to 90% for objects at the survey limit. The 2dFGRS data base is available on the World Wide Web at http://www.mso.anu.edu.au/2dFGRS/.
- ID:
- ivo://CDS.VizieR/VII/226
- Title:
- The 2dF Galaxy Redshift Survey 100k Data Release
- Short Name:
- VII/226
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The 2dF Galaxy Redshift Survey (2dFGRS) is designed to measure redshifts for approximately 250000 galaxies. The 2dFGRS uses the 2dF multifibre spectrograph on the Anglo-Australian Telescope, which is capable of observing 400 objects simultaneously over a 2 degree diameter field. The source catalogue for the survey is a revised and extended version of the APM galaxy catalogue, and the targets are galaxies with extinction-corrected magnitudes brighter than bJ=19.45. The main survey regions are two declination strips, one in the southern Galactic hemisphere spanning 80x15degrees around the South Galactic Pole, and the other in the Northern Galactic hemisphere spanning 75x10degrees along the celestial equator; in addition, there are 99 fields spread over the southern Galactic cap. The survey covers 2000 square degrees and has a median depth of z=0.11. Adaptive tiling is used to give a highly uniform sampling rate of 93% over the whole survey region. The 100k release contains the 102426 objects observed up to 31 January 2001. Redshifts are measured from spectra covering 3600-8000 Angstroms at a two-pixel resolution of 9.0 Angstrom and a median S/N of 13 per pixel. All redshift identifications are visually checked and assigned a quality parameter Q in the range 1-5; Q>=3 redshifts are 98.4% reliable and have an rms uncertainty of 85 km/s. The overall redshift completeness for Q>=3 redshifts is 91.8% but this varies with magnitude from 99% for the brightest galaxies to 90% for objects at the survey limit. The 2dFGRS data base is available on the World Wide Web at http://www.mso.anu.edu.au/2dFGRS. This catalog was extracted from the 2dF Galaxy Redshift Survey 100k release CD-ROMs using the included mSQL database. This catalog comprises the basic spectroscopic information from the best spectrum of each object, that is contained in the extnum=0 rows of the mSQL database.
- ID:
- ivo://CDS.VizieR/VII/241
- Title:
- The 2dF QSO Redshift Survey
- Short Name:
- VII/241
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The final catalogue of the 2dF QSO Redshift Survey (2QZ) is based on Anglo-Australian Telescope 2dF spectroscopic observations of 44576 colour-selected (ub_J_r) objects with 18.25<b_J_< 20.85 selected from automated plate measurement scans of UK Schmidt Telescope (UKST) photographic plates. The 2QZ comprises 23338 quasi-stellar objects (QSOs), 12292 galactic stars (including 2071 white dwarfs) and 4558 compact narrow emission-line galaxies. We obtained a reliable spectroscopic identification for 86 per cent of objects observed with 2dF. We also report on the 6dF QSO Redshift Survey (6QZ), based on UKST 6dF observations of 1564 brighter (16<b_J_<18.25) sources selected from the same photographic input catalogue. In total, we identified 322 QSOs spectroscopically in the 6QZ. The completed 2QZ is, by more than a factor of 50, the largest homogeneous QSO catalogue ever constructed at these faint limits (b_J_<20.85) and high QSO surface densities (35 QSOs/deg^2^). As such, it represents an important resource in the study of the Universe at moderate-to-high redshifts.
- ID:
- ivo://CDS.VizieR/VII/223
- Title:
- The 2dF QSO Redshift Survey. V. The 10k catalogue
- Short Name:
- VII/223
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The 2dF QSO Redshift Survey (2QZ) 10k catalogue is the first release of the 2QZ, containing over 10000 QSOs. There are a total of 20590 sources listed, for which spectra have been obtained using the 2-degree field facility at the Anglo-Australian Observatory. Current data covers an effective area of 289.6deg^2^ for QSO candidates with magnitudes 18.25<b_J_<20.85. The file 2qz_10k.dat contains the names, positions, magnitudes, spectroscopic identifications and redshifts for each of the sources.
- ID:
- ivo://CDS.VizieR/J/MNRAS/392/19
- Title:
- The 2dF-SDSS QSO survey
- Short Name:
- J/MNRAS/392/19
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the final spectroscopic QSO catalogue from the 2dF-SDSS LRG (luminous red galaxy) and QSO (2SLAQ) survey. This is a deep, 18<g<21.85 (extinction corrected), sample aimed at probing in detail the faint end of the broad line active galactic nuclei luminosity distribution at z<=2.6. The candidate QSOs were selected from SDSS photometry and observed spectroscopically with the 2dF spectrograph on the Anglo-Australian Telescope. This sample covers an area of 191.9 deg2 and contains new spectra of 16326 objects, of which 8764 are QSOs and 7623 are newly discovered [the remainder were previously identified by the 2dF QSO Redshift Survey (2QZ) and SDSS]. The full QSO sample (including objects previously observed in the SDSS and 2QZ surveys) contains 12702 QSOs. The new 2SLAQ spectroscopic data set also contains 2343 Galactic stars, including 362 white dwarfs, and 2924 narrow emission-line galaxies with a median redshift of z=0.22.
- ID:
- ivo://CDS.VizieR/J/A+AS/129/399
- Title:
- The ENACS Catalogue. V.
- Short Name:
- J/A+AS/129/399
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the catalogue resulting from the ESO Nearby Abell Cluster Survey (the ENACS), which contains redshifts and magnitudes for 5634 galaxies in the directions of 107 rich, nearby southern Abell cluster candidates. We describe the contents of the catalogue and discuss the results of a comparison between the ENACS catalogue and the COSMOS Galaxy Catalogue. When cross-correlating the two catalogues we find that, at least in the areas of the ENACS clusters, the completeness of the COSMOS catalogue is somewhat lower than was estimated previously for the carefully analyzed and well-calibrated part of the COSMOS catalogue known as the Edinburgh-Durham Southern Galaxy Survey (EDSGC). The galaxy positions in the COSMOS and ENACS catalogues are found to be on the same system to within about one arcsecond. For the clusters for which the photometry in the ENACS and COSMOS catalogues is based on the same survey plates, the two magnitude scales agree very well. We confirm that the photometric calibration in the EDSGC subset of the COSMOS catalogue is of higher quality than in the EDSGC complement. The ENACS galaxy samples are unbiased subsets of the COSMOS catalogue as far as the projected galaxy distribution is concerned, except in only a few cases. We summarize how the ENACS galaxy samples are subsets of the COSMOS catalogues in the ENACS apertures, with respect to magnitude. For the ENACS catalogue as a whole, we describe the apparent incompleteness at faint magnitudes and towards higher redshifts. Finally, we provide some detailed information about the ENACS catalogue that is essential for its proper statistical use and we summarize some facts that must be remembered when selecting subsets of galaxies from it. Objects:
- ID:
- ivo://CDS.VizieR/J/MNRAS/339/652
- Title:
- The FLASH Redshift Survey
- Short Name:
- J/MNRAS/339/652
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The FLAIR Shapley-Hydra (FLASH) redshift survey catalogue consists of 4613 galaxies brighter than b_J_= 16.7 (corrected for Galactic extinction) over a 700-deg^2^ region of sky in the general direction of the Local Group motion. The survey region is a 70x10{deg} strip spanning the sky from the Shapley Supercluster to the Hydra cluster, and contains 3141 galaxies with measured redshifts. Designed to explore the effect of the galaxy concentrations in this direction (in particular the Supergalactic plane and the Shapley Supercluster) upon the Local Group motion, the 68 per cent completeness allows us to sample the large-scale structure better than similar sparsely-sampled surveys. The survey region does not overlap with the areas covered by ongoing wide-angle (Sloan or 2dF) complete redshift surveys. In this paper, the first in a series, we describe the observation and data reduction procedures, the analysis for the redshift errors and survey completeness, and present the survey data. Note that there are some minor change/improvements over the example table published in MNRAS: 1. R.A./Dec. is now J2000 rather than B1950. 2. l/b are now given to 3 decimal places rather than 1 decimal place. 3. Some additional redshifts from NED and ZCAT have been included.
- ID:
- ivo://CDS.VizieR/VII/273
- Title:
- The Half Million Quasars (HMQ) catalogue
- Short Name:
- VII/273
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A quasar catalogue is presented with a total of 510764 objects including 424748 type 1 QSOs and 26623 type 1 AGN complete from the literature to 25 January 2015. Also included are 25015 high-confidence SDSS-based photometric quasars with radio/X-ray associations, 1595 BL Lac objects, and 32783 type 2 objects. Each object is displayed with arcsecond-accurate astrometry, red and blue photometry, redshift, citations, and radio and X-ray associations where present. Also, 114 new spectroscopically confirmed quasars are presented.
