- ID:
- ivo://nasa.heasarc/sdsswhlgc
- Title:
- Sloan Digital Sky Survey DR6 Galaxy Clusters Catalog
- Short Name:
- SDSSWHLGC
- Date:
- 18 Apr 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- Clusters of galaxies in most of the previous catalogs have redshifts z <= 0.3. Using the photometric redshifts of galaxies from the Sloan Digital Sky Survey Data Release 6 (SDSS DR6), the authors identify 39,716 clusters in the redshift range 0.05 < z < 0.6 with more than eight luminous (M_r <= -21) member galaxies. Cluster redshifts are estimated accurately with an uncertainty of less than 0.022. The contamination rate of member galaxies is found to be roughly 20%, and the completeness of member galaxy detection reaches ~90%. Monte Carlo simulations show that the cluster detection rate is more than 90% for massive (M_200 > 2 x 10<sup>14</sup> M_sun, where M_200 is the total mass within the radius in which the mean mass density is 200 times the critical cosmic mass density) clusters of z <= 0.42. The false detection rate is ~5%. The authors obtain the richness, the summed luminosity, and the gross galaxy number within the determined radius for identified clusters. They are tightly related to the X-ray luminosity and temperature of the clusters. Cluster mass is related to the richness and summed luminosity with M_200 ~ R<sup>(1.90+/-0.04)</sup> and M_200 ~ L_r<sup>(1.64+/-0.03)</sup>, respectively. In addition, 790 new candidate X-ray clusters are found by cross-identification of these clusters with the source list of the ROSAT X-ray All-Sky Survey. This table was created by the HEASARC in August 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 .
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- ID:
- ivo://nasa.heasarc/sdssdr10wd
- Title:
- Sloan Digital Sky Survey DR10 New White Dwarf Catalog
- Short Name:
- SDSSDR10WD
- Date:
- 18 Apr 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The authors report the discovery of 9,088 new spectroscopically confirmed white dwarfs and subdwarfs in the Sloan Digital Sky Survey (SDSS) Data Release 10 (DR10). They obtain T<sub>eff</sub>, log g and masses for hydrogen-atmosphere white dwarf stars (DAs) and helium-atmosphere white dwarf stars (DBs), and estimate the calcium/helium abundances for the white dwarf stars with metallic lines (DZs) and carbon/helium for carbon-dominated spectra (DQs). They found 1 central star of a planetary nebula, 2 new oxygen spectra on helium-atmosphere white dwarfs, 71 DQs, 42 hot DO/PG1159s, 171 white dwarf+main-sequence star binaries, 206 magnetic DAHs, 327 continuum-dominated DCs, 397 metal-polluted white dwarfs, 450 helium-dominated white dwarfs, 647 subdwarfs and 6887 new hydrogen-dominated white dwarf stars. The targeted white dwarfs were required to be point sources with clean photometry, and to have USNO-B Catalog counterparts (Monet et al.. 2003, AJ, 125, 984, <a href="https://cdsarc.cds.unistra.fr/ftp/cats/I/284">CDS Cat. I/284</a>). They were also restricted to regions inside the DR7 imaging footprint and required to have colors within the ranges g < 19.2, (u-r) < 0.4, -1 < (u-g) < 0.3, -1 < (g-r) < 0.5 and to have low Galactic extinction A<sub>r</sub> < 0.5 mag. Additionally, targets that did not have (u-r) < -0.1 and (g-r) < -0.1 were required to have USNO proper motions larger than 2 arcseconds per century (20 milliarcseconds per year). Objects satisfying the selection criteria that had not been observed previously by the SDSS were denoted by the WHITEDWARF_NEW target flag, while those with prior SDSS spectra are assigned the WHITEDWARF_SDSS flag. Some of the latter were re-observed with BOSS in order to obtain the extended wavelength coverage that the BOSS spectrograph offers. The color selection used includes DA stars with temperatures above ~14,000 K, helium-atmosphere white dwarfs above ~8000 K, as well as many rarer classes of white dwarfs. Hot subdwarfs (sdB and sdO) were targeted as well. Note that this catalog does not include stars from the earlier SDSS white dwarf catalogs, e.g., Eisenstein et al. (2006, ApJS, 167, 40, available in the HEASARC database as the SDSSDWDSD table), Kleinman et al. (2013, ApJS, 205, 5, available in the HEASARC database as the SDSSDR7WD table).. This table was created by the HEASARC in October 2017 based on an electronic version of Table 6 from the reference paper which was obtained from the CDS as their catalog J/MNRAS/446/4078 file table6.dat. 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:
- 18 Apr 2025
- 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/sdsscvcat
- Title:
- Sloan Digital Sky Survey I/II Cataclysmic Variables Catalog
- Short Name:
- SDSSCVCAT
- Date:
- 18 Apr 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The reference paper completed the series of cataclysmic variables (CVs) identified from the Sloan Digital Sky Survey (SDSS) I and II. The coordinates, magnitudes, and SDSS spectra of 33 more CVs were presented. Among the 33 are eight systems known prior to SDSS (CT Ser, DO Leo, HK Leo, IR Com, V849 Her, V405 Peg, PG1230+226, and HS0943+1404), as well as nine objects recently found through various photometric surveys. Among the systems identified since the SDSS are two polar candidates, two intermediate polar candidates, and one candidate for containing a pulsating white dwarf. A complete summary table of the 285 CVs with spectra from SDSS I/II which were listed in the reference paper and the 7 previous papers in the series is contained herein. This table was created by the HEASARC in January 2012 based on an electronic version of Table 6 from the reference paper which was obtained from the AJ 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:
- 18 Apr 2025
- 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/sdsss82cxo
- Title:
- Sloan Digital Sky Survey Stripe 82 Chandra Source Match Catalog
- Short Name:
- SDSSS82CXO
- Date:
- 18 Apr 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains some of the data from the latest release of the Stripe 82 X-ray (82X) survey point-source catalog, which currently covers 31.3 deg<sup>2</sup> of the Sloan Digital Sky Survey (SDSS) Stripe 82 Legacy field. In total, 6,181 unique X-ray sources are significantly detected with XMM-Newton (> 5 sigma) and Chandra (> 4.5 sigma). This 31 deg<sup>2</sup> catalog release includes data from XMM-Newton cycle AO 13, which approximately doubled the Stripe 82X survey area. The flux limits of the Stripe 82X survey are 8.7 x 10<sup>-16</sup> erg s<sup>-1</sup> cm<sup>-2</sup>, 4.7 x 10<sup>-15</sup> erg s<sup>-1</sup> cm<sup>-2</sup>, and 2.1 x 10<sup>-15</sup> erg s<sup>-1</sup> cm^=2^ in the soft (0.5 - 2.0 keV), hard (2 - 10 keV), and full (0.5 - 10 keV) bands, respectively, with approximate half-area survey flux limits of 5.4 x 10<sup>-15</sup> erg s<sup>-1</sup> cm<sup>-2</sup>, 2.9 x 10<sup>-14</sup> erg s<sup>-1</sup> cm<sup>-2</sup>, and 1.7 x 10<sup>-14</sup> erg s<sup>-1</sup> cm<sup>-2</sup>, respectively. The authors matched the X-ray source lists to available multi-wavelength catalogs, including updated matches to the previous release of the Stripe 82X survey; 88% of the sample is matched to a multi-wavelength counterpart. Due to the wide area of Stripe 82X and rich ancillary multi-wavelength data, including coadded SDSS photometry, mid-infrared WISE coverage, near-infrared coverage from UKIDSS and VISTA Hemisphere Survey (VHS), ultraviolet coverage from GALEX, radio coverage from FIRST, and far-infrared coverage from Herschel, as well as existing ~30% optical spectroscopic completeness, this study is beginning to uncover rare objects, such as obscured high-luminosity active galactic nuclei at high redshift. The Stripe 82X point source catalog is a valuable data set for constraining how this population grows and evolves, as well as for studying how they interact with the galaxies in which they live. The authors derive the XMM-Newton number counts distribution and compare it with their previously reported Chandra log N - log S relations and other X-ray surveys. Throughout this study, the authors adopt a cosmology of H<sub>0</sub> = 70 km s<sup>-1</sup> Mpc<sup>-1</sup>, Omega<sub>M</sub> = 0.27, and Lambda = 0.73. The XMM-Newton and Chandra X-ray sources were matched with sources in the SDSS, WISE, UKIDSS, VHS, GALEX, FIRST and Herschel databases using the maximum likelihood estimator (MLE) method, as discussed in detail in Section 4 of the reference paper. This table contains the list of 1,146 Chandra sources detected in the SDSS Stripe 82. A related table SDSSS82XMM contains the list of 5,220 XMM-Newton sources detected in the SDSS Stripe 82. This table was initially created by the HEASARC in April 2014 based on the machine-readable version of the table ('Properties of SDSS Quasars Detected by Chandra') described in Appendix B1 of the reference paper (LaMassa et al. 2013, MNRAS, 436, 3581) which was obtained from the CDS (their catalog J/MNRAS/436/3581/ file chands82.dat). The present version was created by the HEASARC in January 2017 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/ApJ/817/172">CDS Catalog J/ApJ/817/172</a> file chandra.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/sdsslasqso
- Title:
- Sloan Digital Sky Survey/UKIRT DSS Large Area Survey Matched Quasars Catalog
- Short Name:
- SDSSLASQSO
- Date:
- 18 Apr 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains a catalog of over 130,000 quasar candidates with near-infrared (NIR) photometric properties, with an areal coverage of approximately 1200 deg<sup>2</sup>. This is achieved by matching the Sloan Digital Sky Survey (SDSS) in the optical ugriz bands to the UKIRT Infrared Digital Sky Survey (UKIDSS) Large Area Survey (LAS) in the NIR YJHK bands. The authors match the ~1 million SDSS DR6 Photometric Quasar catalog to Data Release 3 of the UKIDSS LAS (ULAS) and produce a catalog with 130,827 objects with detections in one or more NIR bands, of which 74,351 objects have optical and K-band detections and 42,133 objects have the full nine-band photometry. The majority (~85%) of the SDSS objects were not matched simply because these were not covered by the ULAS. The positional standard deviation of the SDSS Quasar to ULAS matches is 0.1370 arcseconds in RA and 0.1314 arcseconds in Dec. The authors find an absolute systematic astrometric offset between the SDSS Quasar catalog and the UKIDSS LAS, of |RA offset| = 0.025 arcseconds and |Dec offset| = 0.040 arcseconds; they suggest the nature of this offset to be due to the matching of catalog, rather than image, level data. Their matched catalog has a surface density of ~53 deg<sup>-2</sup> for K <= 18.27 objects; tests using this matched catalog, along with data from the UKIDSS Deep Extragalactic Survey, imply that its limiting magnitude is i ~ 20.6. Color-redshift diagrams, for the optical and NIR, show a close agreement between this matched catalog and recent quasar color models at redshift z <~ 2.0, while at higher redshifts, the models generally appear to be bluer than the mean observed quasar colors. This table was created by the HEASARC in September 2012 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/AJ/141/105">CDS Catalog J/AJ/141/105</a> file table4.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/sdssunuqsr
- Title:
- Sloan Digital Sky Survey Unusual Quasars Catalog
- Short Name:
- SDSSUNUQSR
- Date:
- 18 Apr 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- Large spectroscopic surveys have discovered very peculiar and hitherto unknown types of active galactic nuclei (AGN). Such rare objects may hold clues to the accretion history of the supermassive black holes at the centres of galaxies. The authors aim to create a sizeable sample of unusual quasars from the unprecedented spectroscopic database of the Sloan Digital Sky Survey (SDSS). This table contains a catalog of 1005 quasars with unusual spectra in the redshift interval from 0.6 to 4.3. [HEASARC Note: the redshifts in this table actually range from 0.497 to 4.771]. The quasars were selected from the Sloan Digital Sky Survey Data Release 7 (Abazajian et al., 2009, ApJS, 182, 543) by means of Kohonen self-organising maps. The spectra are dominated by either broad absorption lines (42%), unusual red continua (27%), weak emission lines (18%), or conspicuously strong optical and/or UV iron emission (11%). This large sample provides a useful resource for both studying properties and relations of/between different types of unusual quasars and selecting particularly interesting objects, even though the compilation is not aimed at completeness in a quantifiable sense. The spectra are grouped into seven types. The catalogue contains the redshift, the absolute magnitude, the spectral type, the radio loudness parameter, a peculiarity index, and some comments on peculiar spectral features. This table was created by the HEASARC in May 2012 based on CDS table J/A+A/541/A77 file table3.dat. This is a service provided by NASA HEASARC .
