- ID:
- ivo://nasa.heasarc/allwiseagn
- Title:
- AllWISE Catalog of Mid-IR AGNs
- Short Name:
- ALLWISEAGN
- Date:
- 26 Apr 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains an all-sky sample of ~1.4 million active galactic nuclei (AGNs) meeting a two-color infrared photometric selection criterion for AGNs as applied to sources from the Wide-field Infrared Survey Explorer final catalog release (AllWISE). The authors assess the spatial distribution and optical properties of their sample and find that the results are consistent with expectations for AGNs. These sources have a mean density of ~38 AGNs per square degree on the sky, and their apparent magnitude distribution peaks at g ~ 20, extending to objects as faint as g ~ 26. The authors test the AGN selection criterion against a large sample of optically identified stars and determine the "leakage" (that is, the probability that a star detected in an optical survey will be misidentified as a quasi-stellar object (QSO) in their sample) rate to be <= 4.0 x 10<sup>-5</sup>. They conclude that their sample contains almost no optically identified stars (<= 0.041%), making this sample highly promising for future celestial reference frame work as it significantly increases the number of all-sky, compact extragalactic objects. The authors further compare their sample to catalogs of known AGNs/QSOs and find a completeness value of >= 84% (that is, the probability of correctly identifying a known AGN/QSO is at least 84%) for AGNs brighter than a limiting magnitude of R <= 19. This sample includes approximately 1.1 million previously uncataloged AGNs. The WISE survey is an all-sky mid-IR survey at 3.4, 4.6, 12, and 22 microns (W1, W2, W3, and W4, respectively) conducted between 2010 January 7 and August 6, during the cryogenic mission phase, and first made available to the public on 2011 April 14. WISE has angular resolutions of 6.1, 6.4, 6.5, and 12.0 arcseconds in its four bands, respectively. The AllWISE data release, which was used for this work, incorporates data from the WISE Full Cryogenic, 3-Band Cryo, and NEOWISE Post-Cryo survey (Mainzer et al. 2014, ApJ, 792, 30) phases, which were co-added to achieve a depth of coverage ~0.4 mag deeper than previous data releases. AllWISE contains the positions, apparent motions, magnitudes, and point-spread function (PSF)-profile fit information for almost 748 million objects. Astrometric calibration of sources in the WISE catalog was done by correlation with bright stars from the 2MASS point source catalog, and the astrometric accuracy for sources in the AllWISE release was further improved by taking into account the proper motions of these reference stars, taken from the fourth USNO CCD Astrograph Catalog (UCAC4, Zacharias et al. 2013, AJ, 145, 44). A comparison with ICRF sources shows that AllWISE Catalog sources in the brightness range of 8 < W1 < 12 mag have positional accuracies to within 50 mas, and half of these sources have positional accuracies to within 20 mas. For more details on the WISE mission, see Wright et al. (2010, AJ, 140, 1868). The authors took all sources from the AllWISE catalog following Equations (3) and (4) from Mateos et al. (2012, MNRAS, 426, 3271) and they require that all of their sources have S/N >= 5 in the first three bands, as recommended in Mateos et al. (2012); as a further constraint, they limit their results to those with cc_flags = "0000," meaning that the sources are unaffected by known artifacts such as diffraction spikes, persistence, halos, or optical ghosts. In order to characterize the optical properties of their sample, the authors cross-matched it to SDSS-DR12, which is the final data release of SDSS-III (Eisenstein et al. 2011, AJ, 142, 72), within a radial tolerance of R < 1", obtaining 424,366 matches. To determine the fraction of false positive positional matches (that is, incorrectly correlating an object in their sample with a different SDSS object due to random positional agreement), they performed the same match on a scrambled version of their sample coordinates, determining that less than 1% of other cross-matches are false positive positional matches between the two catalogs. The authors also cross-matched their sample sources with he second release of the Large Quasar Astrometric Catalog (LQAC-2; Souchay et al. 2012, A&A, 537, A99), which contains 187,504 quasars, including radio-selected quasars from the ICRF2, optically selected quasars from SDSS, and infrared-selected quasars from 2MASS, and thus represents a robust sample of quasars over a wide range of wavelengths. They find that 93,403 quasars from LQAC-2 have clean detections. The majority of non-detections are due to sources in LQAC-2 that are too faint, having R >~ 19. This table was created by the HEASARC in January 2016 based on the machine-readable version of Table 1 from the reference paper which was obtained from the ApJS web site. This is a service provided by NASA HEASARC .
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- ID:
- ivo://nasa.heasarc/cosxfirmwc
- Title:
- COSMOSFieldX-Ray&FIRDetectedAGNMultiwavelengthPropertiesCatalog
- Short Name:
- COSXFIRMWC
- Date:
- 26 Apr 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The coeval AGN and galaxy evolution and the observed local relations between super-massive black holes (SMBHs) and galaxy properties suggest some connection or feedback between SMBH growth and galaxy build-up. The authors looked for correlations between properties of X-ray detected AGN and their far-infrared (FIR) detected host galaxies, to find quantitative evidences for this connection, highly debated in recent years. They exploit the rich multi-wavelength data set (from X-ray to FIR) that is available in the COSMOS field for a large sample (692 sources) of AGN and their hosts, in the redshift range 0.1 < z < 4, and use X-ray data to select AGN and determine their properties (intrinsic luminosity and nuclear obscuration), and broad-band (from UV to FIR) spectral energy distribution (SED) fitting to derive host galaxy properties, viz., the stellar mass (M<sub>*</sub>) and the star formation rate (SFR). The authors find that the AGN 2-10 keV luminosity (L<sub>X</sub>) and the host galaxy 8-1000 um star formation luminosity (L<sup>SF</sup><sub>IR</sub>) are significantly correlated. However, the average host L<sup>SF</sup><sub>IR</sub> has a flat distribution in bins of AGN L<sub>X</sub>, while the average AGN L<sub>X</sub> increases in bins of host L<sup>SF</sup><sub>IR</sub>, with a logarithmic slope of ~ 0.7, in the redshifts range 0.4 < z < 1.2. In the reference paper, the authors also discuss the comparison between the distribution of these two quantities and the predictions from hydrodynamical simulations. Finally, they find that the average column density (N<sub>H</sub>) shows a positive correlation with the host M<sub>*</sub>, at all redshifts, but not with the SFR (or L<sup>SF</sup><sub>IR</sub>). This translates into a negative correlation with specific SFR. These results are in agreement with the idea that BH accretion and SFRs are correlated, but occur with different variability time scales. The presence of a positive correlation between N<sub>H</sub> and host M<sub>*</sub> suggests that the X-ray N<sub>H</sub> is not entirely due to the circumnuclear obscuring torus, but may also include a contribution from the host galaxy. This table summarizes the multiwavelength properties of the 692 AGN-host systems detected in the COSMOS field both in the X-ray and in the FIR (the X-FIR sample). This table was created by the HEASARC in July 2017, based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/602/A123">CDS Catalog J/A+A/602/A123</a> file table1.dat, which contains the multiwavelength properties of the 692 sources in the X-FIR sample. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/qso
- Title:
- Hewitt&Burbidge(1993)QSOCatalog
- Short Name:
- HB
- Date:
- 26 Apr 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This is (a somewhat condensed form of) the Hewitt & Burbidge (1993) Revised and Updated Catalog of Quasi-Stellar Objects, and contains all then-known (to 1992 December 31) quasi-stellar objects (QSOs) with measured emission redshifts and BL Lac objects. The catalog contains 7315 objects, nearly all of which are quasi-stellar objects, and 89 of which are BL Lac objects. It contains extensive information on names, positions, magnitudes, colors, emission-line redshifts, absorption-line systems, etc. The published version of this catalog (Hewitt & Burbidge 1993, ApJS, 87, 451) typically contained multiple rows on information for each object. This database basically has only the information given in the first row for every object, and is based on the CDS/ADC table VII/158 table1_1.dat.gz. This database was created by the HEASARC in February 2001 based on CDS/ADC Catalog VII/158 (table1_1.dat.gz). This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/intibisag2
- Title:
- INTEGRAL IBIS AGN Catalog Update
- Short Name:
- INTIBISAG2
- Date:
- 26 Apr 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- In the most recent IBIS survey based on observations performed during the first 1000 orbits of INTEGRAL, there are listed 363 high-energy emitters firmly associated with AGN, 107 of which are reported here for the first time. The authors have used X-ray data to image the IBIS 90% error circle of all the AGN in the sample of 107, in order to obtain the correct X-ray counterparts, locate them with arcsecond accuracy and therefore pinpoint the correct optical counterparts. This procedure has led to the optical and spectral characterization of the entire sample. This new set consists of 34 broad line or type 1 AGN, 47 narrow line or type 2 AGN, 18 blazars and 8 sources of unknown class. These eight sources have been associated with AGN from their positional coincidence with 2MASX/Radio/X-ray sources. Seven high-energy emitters have also been included since they are considered to be good AGN candidates. Spectral analysis has been already performed on 55 objects and the results from the most recent and/or best statistical measurements have been collected. For the remaining 52 sources, the authors report the spectral analysis for the first time in this work. They have been able to obtain full X-ray coverage of the sample making use of data from Swift/XRT, XMM-Newton and NuSTAR. In addition to the spectral characterization of the entire sample, this analysis has enabled the authors to identify peculiar sources and by comparing different data sets, highlight flux variability in the 2-10 keV and 20-40 keV bands. In the reference paper, the authors present the X-ray and optical follow-up work on 107 new AGN recently detected by INTEGRAL. Fortunately, they have been able to obtain full X-ray coverage of the entire sample making use of data from the Swift/XRT, Newton-XMM, and NuSTAR archives or through Swift/XRT follow-up observations that they triggered. The HEASARC notes that this table of AGN newly detected by INTEGRAL and not included in the original INTEGRAL IBIS AGN Catalog (Malizia et al. 2012, MNRAS, 426, 1750, available at the HEASARC as the INTIBISAGN table) actually contains 108 AGN plus 8 candidate AGN, for a total of 116 objects, rather than the 107 plus 7 candidate AGN totalling 114 objects that are quoted in the abstract of the reference paper (and stated above). The reason for this discrepancy is not known to the HEASARC. This table was created by the HEASARC in November 2017 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/MNRAS/460/19">CDS Catalog J/MNRAS/460/19</a> files tablea1.dat and refs.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/lbqs
- Title:
- Large Bright Quasar Survey
- Short Name:
- LBQS
- Date:
- 26 Apr 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- Positions, redshifts, and magnitudes for the 1055 quasars in the Large Bright Quasar Survey (LBQS) are presented in a single catalog. Celestial positions have been rederived using the PPM catalog to provide an improved reference frame. Redshifts calculated via cross correlation with a high signal-to-noise ratio composite quasar spectrum are included and the small number of typographic and redshift misidentifications in the discovery papers are corrected. Compared to the discovery papers (references below), 12 quasars that are either fainter than the field magnitude limit or fall outside the final survey area have been deleted, 12 quasars that were discovered subsequent to paper V have been added, 10 redshifts have been corrected, and 13 quasars with either incorrect or degenerate designations (LBQS names) have had their designations corrected. The information in this version of the LBQS Catalog is the same as in Table 4 of the published paper with the following exceptions: (i) the object 0021-0213 has a redshift of 2.348; this value was listed in Table 5 of the paper but was not incorporated in Table 4 of the paper; (ii) the parameter 'Reference' in Table 4 of the published paper (which specified in which paper in the LBQS series the quasar spectrum could be found) has been omitted; and (iii) the parameter 'Notes' in Table 4 of the published paper had two non-blank values: '+' and 'a'; in the HEASARC representation of this catalog we have replaced the Notes value of '+' by 'C', and dropped the Notes value of 'a' (used to indicate objects that had been listed as AGN in earlier papers). This catalog was created by the HEASARC in July 1999 based on a table that was kindly provided by the first author, Paul Hewett, supplemented by documentation created by the CDS/ADC. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/rosatrqq
- Title:
- ROSAT Radio-Quiet Quasars Catalog
- Short Name:
- ROSAT/RQQ
- Date:
- 26 Apr 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- A sample of all radio-quiet quasars or quasars without radio detection taken from the Veron-Cetty - Veron catalog (1993, VERON93, ADC/CDS Cat. VII/166) which were either (i) detected by ROSAT in the ALL-SKY SURVEY (RASS, Voges 1992, in Proc. of the ISY Conference `Space Science', ESA ISY-3, ESA Publications, p.9, ADC/CDS Cat. IX/10), or (ii) detected as targets of pointed observations, or (iii) detected as serendipitous sources in pointed observations that were publicly available in the ROSAT point source catalog (ROSATSRC, Voges et al. 1995, ADC/CDS Cat. IX/11), has been compiled by Yuan et al. (1998, A&A, 330, 108). For all sources, they used the results of the Standard Analysis Software System (SASS, Voges et al. 1992, in Proc. of the ISY Conference `Space Science', ESA ISY-3, ESA Publications, p.223), employing the most recent processing for the Survey data (RASS-II, Voges et al. 1996, ADC/CDS Cat. IX/10). The total number of quasars in this ROSAT Radio-Quiet Quasars Catalog is 846. Sixty-nine of the radio-quiet objects with radio detections have already been presented in a previous paper (Brinkmann, Yuan, and Siebert 1997, Cat. J/A+A/319/413) using the RASS-I results. Seventeen objects were found to be radio-loud from recent radio surveys and were marked in the table. When available, the power law photon indices and the corresponding absorption column densities (NH) were estimated from the two hardness ratios given by the SASS, both with free fitted NH and for Galactic absorption. The unabsorbed X-ray flux densities in the ROSAT band (0.1-2.4keV) were calculated from the count rates using the energy to counts conversion factor for power law spectra and Galactic absorption. The authors used as the photon index the value obtained for the individual source if the estimated 1-{sigma} error was smaller than 0.5, otherwise they used the redshift-dependent mean value (see the paper for details). Notice that the positions of sources in this catalog are not the positions of the X-ray sources, but the optical positions of the quasars as given in the VERON93 Catalog (Wolfgang Brinkmann, 1998 private communication). This database was created by the HEASARC in December 1998, based on CDS/ADC Catalog J/A+A/330/108. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/sdssxmmqso
- Title:
- Sloan Digital Sky Survey (DR5)/XMM-Newton Quasar Survey Catalog
- Short Name:
- SDSSXMMQSO
- Date:
- 26 Apr 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains the 5th Data Release Sloan Digital Sky Survey (DR5 SDSS)/XMM-Newton Quasar Survey Catalog. This catalog contains 792 SDSS DR5 quasars with optical spectra that have been observed serendipitously in the X-rays with XMM-Newton. These quasars cover a redshift range of z = 0.11 - 5.41 and a magnitude range of i = 15.3 - 20.7. Substantial numbers of radio-loud (70) and broad absorption line (51) quasars exist within this sample. Significant X-ray detections at >=2 sigma account for 87% of the sample (685 quasars), and 473 quasars are detected at >=6 sigma, sufficient to allow X-ray spectral fits. For detected sources, ~60% have X-ray fluxes between F(2-10 keV) = (1-10) x 10<sup>-14</sup> erg cm<sup>-2</sup> s<sup>-1</sup>. The authors fit a single power law, a fixed power law with intrinsic absorption left free to vary, and an absorbed power-law model to all quasars with X-ray signal-to-noise ratio >= 6, resulting in a weighted mean photon index Gamma = 1.91 +/- 0.08, with an intrinsic dispersion sigma(Gamma) = 0.38. For the 55 sources (11.6%) that prefer intrinsic absorption, the authors find a weighted mean N<sub>H</sub> = 1.5 +/- 0.3 x 10<sup>21</sup> cm<sup>-2</sup>. They find that Gamma correlates significantly with optical color, Delta(g-i), the optical-to-X-ray spectral index (alpha<sub>ox</sub>), and the X-ray luminosity. While the first two correlations can be explained as artifacts of undetected intrinsic absorption, the correlation between Gamma and X-ray luminosity appears to be a real physical correlation, indicating a pivot in the X-ray slope. This table was created by the HEASARC in July 2009 based on electronic versions of Tables 1 and 2 from the paper which were obtained from the Astrophysical Journal web site. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/sdssnbcqsc
- Title:
- Sloan Digital Sky Survey NBC Quasar Candidate Catalog
- Short Name:
- SDSSQSOCand.
- Date:
- 26 Apr 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The Nonparametric Bayes Classifier (NBC) Quasar Candidate Catalog is a catalog of 100,563 unresolved, UV-excess (UVX) quasar candidates with magnitudes to as faint as 21 in the g-band from 2099 square degrees of the Sloan Digital Sky Survey (SDSS) Data Release One (DR1) imaging data. Existing spectra of 22,737 sources reveals that 22,191 (97.6%) are quasars; accounting for the magnitude dependence of this efficiency, the authors estimate that 95,502 (95.0%) of the objects in the catalog are quasars. Such a high efficiency is unprecedented in broadband surveys of quasars. This "proof-of-concept" sample is designed to be maximally efficient, but still has 94.7% completeness to unresolved, g ~< 19.5, UVX quasars from the DR1 quasar catalog. This efficient and complete selection is the result of the application of a probability density type analysis to training sets that describe the four-dimensional color distribution of stars and spectroscopically confirmed quasars in the SDSS. Specifically, the authors use a nonparametric Bayesian classification, based on kernel density estimation, to parametrize the color distribution of astronomical sources - allowing for fast and robust classification. They further supplement the catalog by providing photometric redshifts and matches to FIRST/VLA, ROSAT, and USNO-B sources. Much more information on the SDSS is available at the project's web site at <a href="http://www.sdss.org/">http://www.sdss.org/</a>. This database table was created by the HEASARC in August 2005 based on CDS table J/ApJS/155/257/table1.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/tartarus
- Title:
- Tartarus: Reduced ASCA AGN Data (Version 3.1)
- Short Name:
- ASCA/AGN
- Date:
- 26 Apr 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The Tartarus database contains the results of a detailed but systematic analysis of ASCA observations of active galactic nuclei (AGN). It contains source and background events files, spectra, ancillary response files and response matrices, images, and assorted light curves for a large number of ASCA AGN observations. Spectral fit results are done by automatic XSPEC fitting. This database table allows easy access to reduced AGN data for the whole community, allowing the maximum scientific return from the data. Availability of publishable light curves, images, and spectra (which can also be readily re-fitted) should be particularly valuable to astronomers with little direct experience in the reduction of X-ray data. Version 3.1 has been created by analyzing all ASCA observing sequences with targets designated as AGN, as indicated by a leading "7" in the ASCA observing sequence number. Version 3.1 contains products for all 611 observing sequences designated as AGN observations. This is a significant improvement over Versions 1 and 2. Moreover, the 611 sequences for which products are available are complete in the sense that either the target object was not detected (in which case an upper limit on GIS2 source counts is given) or the intended AGN target was detected and the data were fully analyzed. In order to obtain the most accurate background subtraction and minimize contamination from any nearby sources, version 3.1 makes more use of custom extraction regions than previous versions. It is expected that version 3.1 will be replaced when the final ASCA calibration is completed. This database table has been created by the Tartarus Team, and they, rather than Imperial College London or the HEASARC, are responsible for the contents. It was ingested by the HEASARC in August, 2005. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/uvqs
- Title:
- UV-Bright Quasar Survey (UVQS) DR1 Catalog
- Short Name:
- UVQS
- Date:
- 26 Apr 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains data from the first data release (DR1) from the UV-bright Quasar Survey (UVQS) for new z ~ 1 active galactic nuclei (AGN) across the sky. Using simple GALEX UV and WISE near-IR color selection criteria, the authors generated a list of 1,450 primary candidates with FUV < 18.5 mag, that is contained in the HEASARC table (entries with source_sample = 'P'). They obtained discovery spectra, primarily on 3m-class telescopes, for 1,040 of these candidates and confirmed 86% as AGN, with redshifts generally at z > 0.5. Including a small set of observed secondary candidates, the authors report the discovery of 217 AGN with GALEX FUV magnitudes < 18 mag that previously had no reported spectroscopic redshifts. These are excellent potential targets for UV spectroscopy before the end of the Hubble Space Telescope mission. The main data products of UVQS are publicly available through the Mikulski Archive for Space Telescopes (MAST). The authors have performed an all-sky survey for z ~ 1, FUV-bright quasars selected from GALEX and WISE photometry. In several of the observing runs, conditions were unexpectedly favorable and we exhausted the primary candidates at certain right ascension ranges. To fill the remaining observing time, they generated a secondary candidate list. This secondary set of 2,010 candidates is also contained in this HEASARC table (entries with source_sample = 'S'). The authors proceeded to obtain discovery-quality long-slit spectra (i.e., low-dispersion, large-wavelength coverage, modest signal-to-noise ratio (S/N) of their UV-bright Quasar Survey (UVQS) candidates in one calendar year. The principal facilities were: (i) the dual Kast spectrometer on the 3m Shane telescope at the Lick Observatory; (ii) the Boller & Chivens (BCS) spectrometer on the Irenee du Pont 100-inch telescope at the Las Campanas Observatory; and (iii) the Calar Alto Faint Object Spectrograph on the CAHA 2.2-meter telescope at the Calar Alto Observatory (CAHA). They acquired an additional ~20 spectra on larger aperture telescopes (Keck/ESI, MMT/MBC, Magellan/MagE) during twilight or under poor observing conditions. Typical exposure times were limited to < ~200s, with adjustments for fainter sources or sub-optimal observing conditions. Table 3 in the reference paper provides a list of the details of the observations of these candidates. From the total candidates list of 3,460 objects, the authors measured high-quality redshifts (redshift quality flag values of 3 or greater) for 1,121 sources. They assumed that every source with a recessional velocity v<sub>r</sub> = z * c < 500 km s<sup>-1</sup> was "Galactic", which they associate with the Galaxy and members of the Local Group. This included sources where the eigenspectra fits were poor yet a low v<sub>r</sub> was indisputable (e.g., stars). Many of these were assigned z = 0 exactly. The remainder of the UVQS sources were assumed to be extragalactic AGN, and the derived redshift information for these sources (which was given in Table 4 of the reference paper) has been incorporated into this HEASARC representation of UVQS. Finally, there were 93 sources with good-quality spectra for which we cannot the authors could not recover a secure redshift. The majority of these have been previously cataloged as blazars (or BL Lac objects). Table 6 in the reference paper lists the sample of these unknown or insecure redshift objects. This table was created by the HEASARC in April 2017 based upon the <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/AJ/152/25">CDS Catalog J/AJ/152/25</a> files table1.dat, table2.dat, and table4.dat. This is a service provided by NASA HEASARC .
