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861. The Deep SWIRE Field (DSF) IV.
ID:
ivo://CDS.VizieR/J/ApJ/714/1305
Title:
The Deep SWIRE Field (DSF) IV.
Short Name:
J/ApJ/714/1305
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a study of a 20cm selected sample in the Deep Spitzer Wide-area InfraRed Extragalactic Legacy Survey Very Large Array Field, reaching a 5{sigma} limiting flux density at the image center of S_1.4GHz_~13.5uJy. In a 0.6x0.6deg^2^ field, we are able to assign an optical/IR counterpart to 97% of the radio sources. Up to 11 passbands from the NUV to 4.5um are then used to sample the spectral energy distribution (SED) of these counterparts in order to investigate the nature of the host galaxies. By means of an SED template library and stellar population synthesis models, we estimate photometric redshifts, stellar masses, and stellar population properties, dividing the sample into three sub-classes of quiescent, intermediate, and star-forming galaxies. We focus on the radio sample in the redshift range 0.3<z<1.3 where we estimate to have a redshift completeness higher than 90% and study the properties and redshift evolution of these sub-populations.
862. The 2dF QSO Redshift Survey
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.
863. The 2dF QSO Redshift Survey. V. The 10k catalogue
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.
864. The Fermi-AT20G catalog
ID:
ivo://CDS.VizieR/J/ApJ/718/587
Title:
The Fermi-AT20G catalog
Short Name:
J/ApJ/718/587
Date:
21 Oct 2021
Publisher:
CDS
Description:
The high-frequency radio sky, like the gamma-ray sky surveyed by the Fermi satellite, is dominated by flat spectrum radio quasars and BL Lac objects at bright flux levels. To investigate the relationship between radio and gamma-ray emission in extragalactic sources, we have cross-matched the Australia Telescope 20 GHz survey catalog (AT20G) with the Fermi-LAT 1 year Point Source Catalog (1FGL). The 6.0sr of sky covered by both catalogs (DEC<0{deg},|b|>1.5{deg}) contains 5890 AT20G radio sources and 604 1FGL gamma-ray sources. The AT20G source positions are accurate to within ~1 arcsec and, after excluding known Galactic sources, 43% of Fermi 1FGL sources have an AT20G source within the 95% Fermi confidence ellipse. Monte Carlo tests imply that at least 95% of these matches are genuine associations. Only five gamma-ray sources (1% of the Fermi catalog) have more than one AT20G counterpart in the Fermi error box. The AT20G matches also generally support the active galactic nucleus (AGN) associations in the First LAT AGN Catalog. We find a trend of increasing gamma-ray flux density with 20GHz radio flux density. The Fermi detection rate of AT20G sources is close to 100% for the brightest 20GHz sources, decreasing to 20% at 1Jy, and to roughly 1% at 100mJy. Eight of the matched AT20G sources have no association listed in 1FGL and are presented here as potential gamma-ray AGNs for the first time. We also identify an alternative AGN counterpart to one 1FGL source. The percentage of Fermi sources with AT20G detections decreases toward the Galactic plane, suggesting that the 1FGL catalog contains at least 50 Galactic gamma-ray sources in the southern hemisphere that are yet to be identified.
865. The Fermi LAT fourth source catalog (4FGL)
ID:
ivo://CDS.VizieR/J/ApJS/247/33
Title:
The Fermi LAT fourth source catalog (4FGL)
Short Name:
J/ApJS/247/33
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the fourth Fermi Large Area Telescope catalog (4FGL) of {gamma}-ray sources. Based on the first eight years of science data from the Fermi Gamma-ray Space Telescope mission in the energy range from 50MeV to 1TeV, it is the deepest yet in this energy range. Relative to the 3FGL catalog, the 4FGL catalog has twice as much exposure as well as a number of analysis improvements, including an updated model for the Galactic diffuse {gamma}-ray emission, and two sets of light curves (one-year and two-month intervals). The 4FGL catalog includes 5064 sources above 4{sigma} significance, for which we provide localization and spectral properties. Seventy-five sources are modeled explicitly as spatially extended, and overall, 358 sources are considered as identified based on angular extent, periodicity, or correlated variability observed at other wavelengths. For 1336 sources, we have not found plausible counterparts at other wavelengths. More than 3130 of the identified or associated sources are active galaxies of the blazar class, and 239 are pulsars.
866. The Fermi LAT sky as seen by INTEGRAL/IBIS
ID:
ivo://CDS.VizieR/J/ApJ/706/L7
Title:
The Fermi LAT sky as seen by INTEGRAL/IBIS
Short Name:
J/ApJ/706/L7
Date:
21 Oct 2021
Publisher:
CDS
Description:
In this Letter we present the result of the cross correlation between the fourth INTEGRAL/IBIS soft gamma-ray catalog, in the range 20-100keV, and the Fermi LAT bright source list of objects emitting in the 100MeV-100GeV range. The main result is that only a minuscule part of the more than 720 sources detected by INTEGRAL and the population of 205 Fermi LAT sources are detected in both spectral regimes. This is in spite of the mCrab INTEGRAL sensitivity for both galactic and extragalactic sources and the breakthrough, in terms of sensitivity, achieved by Fermi at MeV-GeV energies. The majority of the 14 Fermi LAT sources clearly detected in the fourth INTEGRAL/IBIS catalog are optically identified active galactic nuclei (10) complemented by two isolated pulsars (Crab and Vela) and two high-mass X-ray binaries (LS I +61 303 and LS 5039). Two more possible associations have been found: one is 0FGL J1045.6-5937, possibly the counterpart at high energy of the massive colliding wind binary system Eta Carinae, discovered to be a soft gamma ray emitter by recent INTEGRAL observations and 0FGL J1746.0-2900 coincident with IGR J17459-2902, but still not identified with any known object at lower energy. For the remaining 189 Fermi LAT sources no INTEGRAL counterpart was found and we report the 2{sigma} upper limit in the energy band 20-40keV.
867. The Gaia-WISE extragalactic astrometric catalog
ID:
ivo://CDS.VizieR/J/ApJS/236/37
Title:
The Gaia-WISE extragalactic astrometric catalog
Short Name:
J/ApJS/236/37
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Gaia mission has detected a large number of active galactic nuclei (AGNs) and galaxies, but these objects must be identified among the thousandfold more numerous stars. Extant astrometric AGN catalogs do not have the uniform sky coverage required to detect and characterize the all-sky, low-multipole proper motion signals produced by the barycenter motion, gravitational waves, and cosmological effects. To remedy this, we present an all-sky sample of 567,721 AGNs in Gaia Data Release 1, selected using WISE two-color criteria. The catalog has fairly uniform sky coverage beyond the Galactic plane, with a mean density of 12.8 AGNs per square degree. The objects have magnitudes ranging from G=8.8 down to Gaia's magnitude limit, G=20.7. The catalog is approximately 50% complete but suffers from low stellar contamination, roughly 0.2%. We predict that the end-of-mission Gaia proper motions for this catalog will enable detection of the secular aberration drift to high significance (23{sigma}) and will place an upper limit on the anisotropy of the Hubble expansion of about 2%.
868. The gNLS1 galaxy PKS 2004-447. VLBI images
ID:
ivo://CDS.VizieR/J/A+A/588/A146
Title:
The gNLS1 galaxy PKS 2004-447. VLBI images
Short Name:
J/A+A/588/A146
Date:
21 Oct 2021
Publisher:
CDS
Description:
Gamma-ray-detected radio-loud narrow-line Seyfert 1 (g-NLS1) galaxies constitute a small but interesting sample of the g-ray-loud AGN. The radio-loudest g-NLS1 known, PKS 2004-447, is located in the southern hemisphere and is monitored in the radio regime by the multiwavelength monitoring programme TANAMI. We aim for the first detailed study of the radio morphology and long-term radio spectral evolution of PKS 2004-447, which are essential for understanding the diversity of the radio properties of g-NLS1s. The TANAMI VLBI monitoring program uses the Australian Long Baseline Array (LBA) and telescopes in Antarctica, Chile, New Zealand, and South Africa to monitor the jets of radio-loud active galaxies in the southern hemisphere. Lower resolution radio flux density measurements at multiple radio frequencies over four years of observations were obtained with the Australia Telescope Compact Array (ATCA). The TANAMI VLBI image at 8.4GHz shows an extended one-sided jet with a dominant compact VLBI core. Its brightness temperature is consistent with equipartition, but it is an order of magnitude below other g-NLS1s with the sample value varying over two orders of magnitude. We find a compact morphology with a projected large-scale size <11kpc and a persistent steep radio spectrum with moderate flux-density variability. PKS 2004-447 appears to be a unique member of the g-NLS1 sample. It exhibits blazar-like features, such as a flat featureless X-ray spectrum and a core-dominated, one-sided parsec-scale jet with indications for relativistic beaming. However, the data also reveal properties atypical for blazars, such as a radio spectrum and large-scale size consistent with compact-steep-spectrum (CSS) objects, which are usually associated with young radio sources. These characteristics are unique among all g-NLS1s and extremely rare among g-ray-loud AGN.
869. The Half Million Quasars (HMQ) catalogue
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.
870. The Hubble Catalog of Variables
ID:
ivo://CDS.VizieR/J/A+A/630/A92
Title:
The Hubble Catalog of Variables
Short Name:
J/A+A/630/A92
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Hubble Catalog of Variables (HCV) is the first full, homogeneous, catalog of variable sources found in the Hubble Source Catalog (HSC), which is built out of publicly available images obtained with the WFPC2, ACS and WFC3 instruments onboard the Hubble Space Telescope. The HCV is the deepest catalog of variables available. It includes variable stars in our Galaxy and nearby galaxies, as well as transients and variable active galactic nuclei. The HCV contains 84428 candidate variable sources (out of 3.7 million HSC sources that were searched for variability) with V<=27mag; for 11115 of them the variability is detected in more than one filter. The data points in a light curve range from 5 to 120, the time baseline ranges from under a day to over 15 years, while ~8% of variables have amplitudes in excess of 1mag.