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881. The Million Quasars (Milliquas) catalog (V5.2)
ID:
ivo://CDS.VizieR/VII/280
Title:
The Million Quasars (Milliquas) catalog (V5.2)
Short Name:
VII/280
Date:
21 Oct 2021
Publisher:
CDS
Description:
This is a compendium of 607,208 type-I QSOs and AGN, largely complete from the literature to 5-August-2017, including the release of SDSS-DR14. Also included are ~1.35M high-confidence (80%+ likelihood) quasar candidates from the NBCKDE, NBCKDE-v3, XDQSO, AllWISE and Peters photometric quasar catalogs (citations in Note 7 below) and from all-sky radio/X-ray associated objects which are calculated here. Type-II and Bl Lac objects are also included, bringing the total count to 1,998,464. Changes from version 5.1 are: (1) SDSS-DR14 and SDSS-DR14Q have been added, using the processing rules from the Half Million Quasars catalog (HMQ: Flesch 2015PASA...32...10F). (2) WISE quasar candidates have been added from Secrest et al, 2015, Cat. J/ApJS/221/12; these are ~430K candidates over the whole sky for which 2-color optical objects were found within a 2-arcsec radius. They have been processed into pQSOs from calibration against the SDSS-DR12Q multi-class superset, and photometric redshifts obtained using the four-color based method from the HMQ appendix 2. The four colors used were B-R, R-W1, W1-W2 & W2-W3. (3) Type-II narrow emission-line galaxies, (NELGs, class='N') are added as the luminosity class corresponding to the type-I AGN galaxies. High-luminosity type-II NLAGN (class='K') correspond to the type-I quasars. The NLAGN/NELG divider is the same luminosity/psf function which separates QSOs from AGNs. Type-II NELGs include unquantified contamination by LINERs and probably a few starbursts which eluded removal, so it serves as a catch-all category presented for completeness, rather than as a strict type-II class. (4) Small publications to 5 August 2017 have been added. (5) Positional fixes (of about 2 arcsec) have been applied to ~150 objects. Low-confidence or questionable objects (so deemed by their researchers) are not included in Milliquas. Additional quality cuts can be applied as detailed in Flesch 2015PASA...32...10F). Multiple lensed images are excluded and only the brightest one kept. The aim here is to present one unique reliable object per each data row. The catalog format is simple, each object is shown as one line bearing the J2000 coordinates, its original name, object class, red and blue optical magnitudes, PSF class, redshift, the citations for the name and redshift, plus up to four radio/X-ray identifiers where applicable. This catalog can be cited as Milliquas, Flesch E., 2015PASA...32...10F which was the published version of this catalog as at 2015 after the release of SDSS-DR12. Questions/comments/praise/complaints may be directed to me at eric(at)flesch.org.
882. The Molonglo Southern 4Jy sample. I
ID:
ivo://CDS.VizieR/J/AJ/131/100
Title:
The Molonglo Southern 4Jy sample. I
Short Name:
J/AJ/131/100
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have defined a complete sample of 228 southern radio sources at 408MHz with integrated flux densities S(408)>4.0Jy, Galactic latitude |b|>10{deg}, and declination -85{deg}<{delta}<-30{deg}. The main finding survey used was the Molonglo Reference Catalogue (Cat. <VIII/16>). Sources in the sample were imaged at 843MHz with the Molonglo Observatory Synthesis Telescope to obtain positions accurate to about 1", as well as flux densities and angular sizes.
883. The Molonglo Southern 4Jy sample. II
ID:
ivo://CDS.VizieR/J/AJ/131/114
Title:
The Molonglo Southern 4Jy sample. II
Short Name:
J/AJ/131/114
Date:
21 Oct 2021
Publisher:
CDS
Description:
Of the 228 sources in the Molonglo Southern 4Jy sample (MS4, Cat. J/AJ/131/100), the 133 with angular sizes <35" have been imaged at 5GHz at 2"-4" resolution with the Australia Telescope Compact Array. More than 90% of the sample has been reliably optically identified, either on the plates of the UK Schmidt Southern Sky Survey or on R-band CCD images made with the Anglo-Australian Telescope.
884. The 54-month Palermo BAT-survey catalogue
ID:
ivo://CDS.VizieR/J/A+A/524/A64
Title:
The 54-month Palermo BAT-survey catalogue
Short Name:
J/A+A/524/A64
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the Second Palermo Swift-BAT hard X-ray catalogue obtained by analysing data acquired in the first 54 months of the Swift mission. Using our software dedicated to the analysis of data from coded mask telescopes, we analysed the BAT survey data in three energy bands (15-30keV, 15-70keV, 15-150keV), obtaining a list of 1256 detections above a significance threshold of 4.8 standard deviations. The identification of the source counterparts is pursued using two strategies: the analysis of field observations of soft X-ray instruments and cross-correlation of our catalogue with source databases. The survey covers 50% of the sky to a 15-150keV flux limit of 1.0x10^-11^erg/cm2/s and 9.2x10^-12^erg/cm2/s for |b|<10 and |b|>10, respectively. The Second Palermo Swift-BAT hard X-ray catalogue includes 1079 (~86%) hard X-ray sources with an associated counterpart (26 with a double association and 2 with a triple association) and 177 BAT excesses (~14%) that still lack a counterpart. The distribution of the BAT sources among the different object classes consists of ~19% Galactic sources, ~57% extragalactic sources, and ~10% sources with a counterpart at softer energies whose nature has not yet been determined. About half of the BAT associated sources lack a counterpart in the ROSAT catalogues. This suggests that either moderate or strong absorption may be preventing their detection in the ROSAT energy band. The comparison of our BAT catalogue with the Fermi Large Area Telescope First Source Catalogue identifies 59 BAT/Fermi correspondences: 48 blazars, 3 Seyfert galaxies, 1 interacting galaxy, 3 high mass X-ray binaries, and 4 pulsars/supernova remnants. This small number of correspondences indicates that different populations make the sky shine in these two different energy bands.
885. The 105-month Swift-BAT all-sky hard X-ray survey
ID:
ivo://CDS.VizieR/J/ApJS/235/4
Title:
The 105-month Swift-BAT all-sky hard X-ray survey
Short Name:
J/ApJS/235/4
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a catalog of hard X-ray sources detected in the first 105-months of observations with the Burst Alert Telescope (BAT) coded-mask imager on board the Swift observatory. The 105-month Swift-BAT survey is a uniform hard X-ray all-sky survey with a sensitivity of 8.40x10^-12^erg/s/cm^2^ over 90% of the sky and 7.24x10^-12^erg/s/cm^2^ over 50% of the sky in the 14-195keV band. The Swift-BAT 105-month catalog provides 1632 (422 new detections) hard X-ray sources in the 14-195 keV band above the 4.8{sigma} significance level. Adding to the previously known hard X-ray sources, 34% (144/422) of the new detections are identified as Seyfert active galactic nuclei (AGNs) in nearby galaxies (z<0.2). The majority of the remaining identified sources are X-ray binaries (7%, 31) and blazars/BL Lac objects (10%, 43). As part of this new edition of the Swift-BAT catalog, we release eight-channel spectra and monthly sampled light curves for each object in the online journal and at the Swift-BAT 105-month website.
886. The nature of hyper luminous infrared galaxies
ID:
ivo://CDS.VizieR/J/A+A/654/A117
Title:
The nature of hyper luminous infrared galaxies
Short Name:
J/A+A/654/A117
Date:
22 Feb 2022
Publisher:
CDS
Description:
Hyperluminous infrared galaxies (HLIRGs) are shown to have been more abundant in early epochs. The small samples used in earlier studies are not sufficient to draw robust statistical conclusions regarding the physical properties and the power sources of these extreme infrared (IR) bright galaxies. We make use of multi-wavelength data of a large hyper luminous galaxy sample to derive the main physical properties, such as stellar mass, star formation rate (SFR), volume density, and the contribution to the cosmic stellar mass density and the cosmic SFR density. We also study the black hole (BH) growth rate and its relationship with the SFR of the host galaxy. We selected 526 HLIRGs in three deep fields (Bootes, Lockman-Hole, and ELAIS-N1) and adopted two spectral energy distribution (SED) fitting codes: CIGALE, which assumes energy balance, and CYGNUS, which is based on radiative transfer models and does not adopt an energy balance principle. We used two different active galactic nucleus (AGN) models in CIGALE and three AGN models in CYGNUS to compare results that were estimated using different SED fitting codes and a range of AGN models. The stellar mass, total IR luminosity, and AGN luminosity agree well among different models, with a typical median offset of 0.1dex. The SFR estimates show the largest dispersions (up to 0.5dex). This dispersion has an impact on the subsequent analysis, which may suggest that the previous contradictory results could partly have been due to the different choices in methods. HLIRGs are ultra-massive galaxies, with 99% of them having stellar masses larger than 10^11^M_{sun}_. Our results reveal a higher space density of ultra-massive galaxies than what was found by previous surveys or predicted via simulations. We find that HLIRGs contribute more to the cosmic SFR density as redshift increases. In terms of BH growth, the two SED fitting methods provide different results. We can see a clear trend in whereby SFR decreases as AGN luminosity increases when using CYGNUS estimates. This may possibly imply quenching by AGN in this case, whereas this trend is much weaker when using CIGALE estimates. This difference is also influenced by the dispersion between SFR estimates obtained by the two codes.
887. The [OIII] emission line in SDSS AGNs
ID:
ivo://CDS.VizieR/J/ApJ/737/71
Title:
The [OIII] emission line in SDSS AGNs
Short Name:
J/ApJ/737/71
Date:
21 Oct 2021
Publisher:
CDS
Description:
We use homogeneous samples of radio-quiet Seyfert 1 galaxies and QSOs selected from the Sloan Digital Sky Survey to investigate the connection between the velocity shift and the equivalent width (EW) of the [OIII]{lambda}5007 emission line, and their correlations with physical parameters of active galactic nuclei (AGNs). We find a significant and negative correlation between the EW of the core component, EW(core), and the blueshift of either the core (the peak), the wing, or the total profile of [OIII] emission; it is fairly strong for the blueshift of the total profile in particular. However, both quantities (EW and velocity shift) generally have only weak, if any, correlations with fundamental AGN parameters such as the nuclear continuum luminosity at 5100{AA} (L_5100_), black hole mass (M_BH_), and the Eddington ratio (L/L_Edd_); these correlations include the classical Baldwin effect of EW(core), an inverse Baldwin effect of EW(wing), and the relationship between velocity shifts and L/L_Edd_. Our findings suggest that both the large object-to-object variation in the strength of [OIII] emission and the blueshift-EW(core) connection are not governed primarily by fundamental AGN parameters such as L_5100_, M_BH_, and L/L_Edd_. We propose that the interstellar medium conditions of the host galaxies play a major role instead in the diversity of the [OIII] properties in active galaxies. This suggests that the use of [OIII]{lambda}5007 luminosity as a proxy of AGN luminosity does not depend strongly on the above-mentioned fundamental AGN parameters.
888. The OPTX project. III.
ID:
ivo://CDS.VizieR/J/ApJ/703/2160
Title:
The OPTX project. III.
Short Name:
J/ApJ/703/2160
Date:
21 Oct 2021
Publisher:
CDS
Description:
We compare the optical spectral types with the X-ray spectral properties for a uniformly selected (sources with fluxes greater than the 3{sigma} level and above a flux limit of f(2-8keV)>3.5x10^-15^erg/cm^2^/s), highly spectroscopically complete (>80% for f(2-8keV)>10^-14^erg/cm^2^/s and >60% below) 2-8keV X-ray sample observed in three Chandra fields (CLANS, CLASXS, and the CDF-N) that cover ~1.2deg^2^. For our sample of 645 spectroscopically observed sources, we confirm that there is significant overlap of the X-ray spectral properties, as determined by the effective photon indices, {Gamma}_eff_, obtained from the ratios of the 0.5-2keV to 2-8keV counts, for the different optical spectral types. Thus, one cannot use the X-ray spectral classifications and the optical spectral classifications equivalently. Since it is not understood how X-ray and optical classifications relate to the obscuration of the central engine, we strongly advise against a mixed classification scheme, as it can only complicate the interpretation of X-ray AGN samples.
889. The simultaneous optical-to-X-ray SED of AGNs
ID:
ivo://CDS.VizieR/J/ApJS/187/64
Title:
The simultaneous optical-to-X-ray SED of AGNs
Short Name:
J/ApJS/187/64
Date:
21 Oct 2021
Publisher:
CDS
Description:
We report Swift observations of a sample of 92 bright soft X-ray selected active galactic nuclei (AGNs). This sample represents the largest number of AGNs observed to study the spectral energy distribution (SED) of AGNs with simultaneous optical/UV and X-ray data. The principal motivation of this study is to understand the SEDs of AGNs in the optical/UV to X-ray regime and to provide bolometric corrections which are important in determining the Eddington ratio L/L_Edd_. In particular, we rigorously explore the dependence of the UV-EUV contribution to the bolometric correction on the assumed EUV spectral shape. We find strong correlations of the spectral slopes {alpha}_X_ and {alpha}_UV_ with L/L_Edd_.
890. The Swift/BAT hard X-ray transient monitor
ID:
ivo://CDS.VizieR/J/ApJS/209/14
Title:
The Swift/BAT hard X-ray transient monitor
Short Name:
J/ApJS/209/14
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Swift/Burst Alert Telescope (BAT) hard X-ray transient monitor provides near real-time coverage of the X-ray sky in the energy range 15-50 keV. The BAT observes 88% of the sky each day with a detection sensitivity of 5.3 mCrab for a full-day observation and a time resolution as fine as 64s. The three main purposes of the monitor are (1) the discovery of new transient X-ray sources, (2) the detection of outbursts or other changes in the flux of known X-ray sources, and (3) the generation of light curves of more than 900 sources spanning over eight years. The primary interface for the BAT transient monitor is a public Web site. Between 2005 February 12 and 2013 April 30, 245 sources have been detected in the monitor, 146 of them persistent and 99 detected only in outburst. Among these sources, 17 were previously unknown and were discovered in the transient monitor. In this paper, we discuss the methodology and the data processing and filtering for the BAT transient monitor and review its sensitivity and exposure. We provide a summary of the source detections and classify them according to the variability of their light curves. Finally, we review all new BAT monitor discoveries. For the new sources that are previously unpublished, we present basic data analysis and interpretations.