- ID:
- ivo://nasa.heasarc/shkgalaxy
- Title:
- Shakhabazian (Shk) Compact Groups of Galaxies: Individual Galaxies Data
- Short Name:
- Shk.(Gal.)
- Date:
- 28 Jun 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The largest survey of compact galaxy groups was published by Shakhbazian et al. (the CDS catalog VII/89, implemented by the HEASARC as the SHK database table). This present catalog provides accurate positions of the individual galaxies in the groups; photometric properties of the Southern sky (delta not greater than +2.5 degrees) are evaluated on the basis of the COSMOS/UKST catalog of the Southern sky. This catalog contains 373 groups; this number differs from the number in Shakhbazian's list (377 groups) by the following: (i) there are no data for groups 001 (already published by other authors), 206 and 241 (could not be re-identified), 252 (this is identical with 214), 301 and 353 (could not be re-identified); (ii) Group 328 was published twice (in North and South); and (iii) Group 340 was divided in two parts (340 and 340a), according to Bettoni and Fasano ([BF95]=1995AJ....109...32B). This HEASARC version of the catalog contains a total of 3435 individual galaxies identified as members of the compact groups, 2574 from the northern part of this survey (taken from the ADS Catalog VII/196 file north.dat), and 861 from the southern part of this survey (extracted from the 10746 entries in the ADS Catalog VII/196 file south.dat by including only entries corresponding to bona fide group members). This database table was created by the HEASARC in June, 2000, based on the CDS Catalog VII/196 (files north.dat and south.dat). This is a service provided by NASA HEASARC .
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- ID:
- ivo://nasa.heasarc/hiiregion
- Title:
- Sharpless H II Regions
- Short Name:
- Sharpless
- Date:
- 28 Jun 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This database table is derived from data contained in the Sharpless Catalogue of H II regions. The original catalog was published in 1959 in the Astrophysical Journal Supplement Series (number 41, pages 257- 280). The original card deck was in the 026 punch and this was converted to a 029 deck. Many of the quantities in this version of the catalog were not in the published catalog. The epochs of the precessed equatorial coordinates were determined empirically from the data as given on the computer cards. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/sigorixmm
- Title:
- Sigma Orionis Cluster XMM-Newton X-Ray Point Source Catalog
- Short Name:
- SIGORIXMM
- Date:
- 28 Jun 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains some of the results of an analysis of the full EPIC field in an XMM-Newton observation of the young (~2 - 4 Myr) cluster around the hot star sigma Orionis. The authors have detected 175 X-ray sources, 88 of which have been identified with cluster members, including very low-mass stars down to the substellar limit. They detected eleven new possible candidate members from the 2MASS (<a href="https://cdsarc.cds.unistra.fr/ftp/cats/II/246">CDS Cat. <II/246></a>) catalog. The authors find that late-type stars have a median log L<sub>X</sub>/L<sub>bol</sub> ~ -3.3, i.e. very close to the saturation limit. They detected significant variability in ~ 40% of late-type members or candidates, including 10 flaring sources; rotational modulation was detected in one K-type star and possibly in another 3 or 4 stars. Spectral analysis of the brightest sources shows typical quiescent temperatures in the range T<sub>1</sub> ~ 0.3 - 0.8 keV and T<sub>2</sub> ~ 1 - 3 keV, with subsolar abundances Z ~ 0.1 - 0.3 solar, similar to what is found in other star-forming regions and associations. The authors find no significant difference in the spectral properties of classical and weak-lined T Tauri stars, although classical T Tauri stars tend to be less X-ray luminous than weak-lined T Tauri stars. XMM-Newton observations of the sigma Ori cluster, centered on the hot star sigma Ori AB, were carried out as part of the Guaranteed Time of Roberto Pallavicini using both the EPIC MOS and PN cameras and the RGS instrument. The observation (ID 0101440301) started at 21:47 UT on March 23, 2002 and ended at 9:58 UT on March 24, 2002, for a total duration of 43 ks. The EPIC cameras were operated in Full Frame mode using the thick filter. This table contains the combined list of 88 X-ray sources positionally (<= 5") associated with confirmed or candidate cluster members, and 66 X-ray sources with no such positional associations, detected above a significance threshold of 5 sigma. The two X-ray sources (source numbers 67 and 167) with 2 possible positional associations are listed twice, once for each positional association, with the X-ray information repeated. Thus, there are 156 entries in this HEASARC table. This table was created by the HEASARC in May 2007 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/446/501">CDS catalog J/A+A/446/501</a> files tablea1.dat and tableb.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/sdssbalqso
- Title:
- Sloan Digital Sky Survey Broad Absorption Line Quasars Catalog: 3rd Data Release
- Short Name:
- SDSSBALQSO
- Date:
- 28 Jun 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The Sloan Digital Sky Survey (SDSS) Broad Absorption Line (BAL) Quasars Catalog (based on the 3rd SDSS Data Release) contains a total of 4784 unique BAL quasars from the SDSS DR3 (CDS Cat. <VII/243>). An automated algorithm was used to match a continuum to each quasar and to identify regions of flux at least 10% below the continuum over a velocity range of at least 1000 km/s in the C IV and Mg II absorption regions. The model continuum was selected as the best-fit match from a set of template quasar spectra binned in luminosity, emission line width, and redshift z, with the power-law spectral index and amount of dust reddening as additional free parameters. The authors characterize their sample through the traditional 'balnicity' index BI and a revised absorption index AI, as well as through parameters such as the width, outflow velocity, fractional depth, and number of troughs. From a sample of 16,883 quasars at 1.7 <= z <= 4.38, they identify 4386 (26.0%) quasars with broad C IV absorption, of which 1756 (10.4%) satisfy traditional selection criteria. From a sample of 34,973 quasars at 0.5 <= z <= 2.15, they identify 457 (1.31%) quasars with broad Mg II absorption, 191 (0.55%) of which satisfy traditional selection criteria. They find that BAL quasars may have broader emission lines on average than other quasars. 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 table was created by the HEASARC in July 2008 based on CDS catalog J/ApJS/165/1 file table4.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/sdssbalqs2
- Title:
- Sloan Digital Sky Survey Broad Absorption Line Quasars Catalog: 5th Data Release
- Short Name:
- SDSSBALQS2
- Date:
- 28 Jun 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains a catalog of 5035 broad absorption line (BAL) quasars (QSOs) in the Sloan Digital Sky Survey (SDSS) Data Release 5 (DR5) QSO catalog that have absorption troughs covering a continuous velocity range greater than or equal to 2000 km s<sup>-1</sup>. The authors have fitted ultraviolet (UV) continua and line emission in each case, enabling them to report common diagnostics of BAL strengths and velocities in the range from -25,000 to 0 km s<sup>-1</sup> for Si IV 1400 Angstroms, C IV 1549 A, Al III 1857 A, and Mg II 2799 A. The authors calculate these diagnostics using the spectrum listed in the DR5 QSO catalog, and also for spectra from additional SDSS observing epochs when available. They confirm and extend previous findings that BAL QSOs are more strongly reddened in the rest-frame UV than non-BAL QSOs, and that BAL QSOs are relatively X-ray weak compared to non-BAL QSOs. The observed BAL fraction is dependent on the spectral signal-to-noise ratio (S/N); for higher S/N sources, the authors find an observed BAL fraction of about 15%. BAL QSOs show a similar Baldwin effect as for non-BAL QSOs, in that their C IV emission equivalent widths decrease with increasing continuum luminosity. However, BAL QSOs have weaker C IV emission in general than do non-BAL QSOs. Sources with higher UV luminosities are more likely to have higher-velocity outflows, and the BAL outflow velocity and UV absorption strength are correlated with relative X-ray weakness. These results are in qualitative agreement with models that depend on strong X-ray absorption to shield the outflow from overionization and enable radiative acceleration. In a scenario in which BAL trough shapes are primarily determined by outflow geometry, observed differences in Si IV and C IV trough shapes would suggest that some outflows have ion-dependent structure. The authors fit SDSS spectra using the algorithm of Gibson et al. (2008, ApJ, 675, 985), which we summarize here. For QSOs at z >= 1.7, their continuum model is a power law reddened using the Small Magellanic Cloud (SMC) reddening curve of Pei (1992, ApJ, 395, 130). For QSOs at lower redshifts, the authors use a fourth- or sixth-degree polynomial; in their experience this nonphysical model is able to reproduce well the complex continuum at longer wavelengths. They initially fit regions that are generally free from strong absorption or emission features: 1250-1350, 1700-1800, 1950-2200, 2650-2710, 2950-3700, 3950-4050, 4140-4270, 4400-4800, 5100-6400, and > 6900 Angstroms. They then iteratively fit the continuum, ignoring at each step wavelength bins that deviate by more than 3 sigma from the current fit in order to exclude strong absorption and emission features. They fit Voigt profiles to the strongest emission lines expected in the spectrum: Si IV 1400, C IV 1549, Al III 1857, C III 1909, and Mg II 2799. These wavelengths are taken from the SDSS vacuum wavelength list used by the SDSS pipeline to determine emission-line redshifts. 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 table was created by the HEASARC in April 2009 based on the machine-readable version of Table 1 from the reference paper obtained from the ApJ web site. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/sdsswhlgc
- Title:
- Sloan Digital Sky Survey DR6 Galaxy Clusters Catalog
- Short Name:
- SDSSWHLGC
- Date:
- 28 Jun 2024
- 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 10^14 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^(1.90+/-0.04)^ and M_200 ~ L_r^(1.64+/-0.03)^, 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 .
- ID:
- ivo://nasa.heasarc/sdssdr10wd
- Title:
- Sloan Digital Sky Survey DR10 New White Dwarf Catalog
- Short Name:
- SDSSDR10WD
- Date:
- 28 Jun 2024
- 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, CDS Cat. I/284). 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/sdssdr7wd
- Title:
- Sloan Digital Sky Survey DR7 White Dwarf Catalog
- Short Name:
- SDSSDR7WD
- Date:
- 28 Jun 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains a new catalog of spectroscopically confirmed white dwarf stars from the Sloan Digital Sky Survey (SDSS) Data Release 7 (DR7) spectroscopic catalog. The authors find 20,407 white dwarf spectra, representing 19,712 stars, and provide atmospheric model fits to 14,120 DA and 1011 DB white dwarf spectra from 12,843 and 923 stars, respectively. These numbers represent more than a factor of two increase in the total number of white dwarf stars from the previous SDSS white dwarf catalogs based on DR4 data. The distribution of subtypes varies from previous catalogs due to the authors' more conservative, manual classifications of each star in our catalog, supplementing their automatic fits. In particular, they find a large number of magnetic white dwarf stars whose small Zeeman splittings mimic increased Stark broadening that would otherwise result in an overestimated log g if fit as a non-magnetic white dwarf. The authors calculate mean DA and DB masses for their clean, non-magnetic sample and find the DB mean mass is statistically larger than that for the DAs. This table lists the 20,407 white dwarf spectra corresponding to 19,712 distinct stars. This table was created by the HEASARC in January 2013 based on the electronic version of Table 2 from the reference paper which was obtained from the ApJS web site. One duplicate entry was removed from the table in June 2019. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/sdsswdsd
- Title:
- SloanDigitalSkySurveyDR4WhiteDwarf&HotSubdwarfCatalog
- Short Name:
- SDSSWDSD
- Date:
- 28 Jun 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This is the Sloan Digital Sky Survey (SDSS) Data Release 4 (DR4) Catalog of White Dwarfs (WDs) and Hot Subdwarf (SD) stars. It contains 9316 spectroscopically confirmed white dwarfs which have been selected through photometric cuts and spectroscopic modeling, backed up by a set of visual inspections. About 6000 of the WD stars are new discoveries, roughly doubling the number of spectroscopically confirmed WD stars. The authors have analyzed the stars by performing temperature and surface gravity fits to grids of pure hydrogen and helium atmospheres. Among the rare outliers are a set of presumed helium-core DA WDs with estimated masses below 0.3 solar masses, including two candidates that may be the lowest-mass WDs yet found. This catalog also contains a list of 928 hot SD stars. The SDSS DR4 (Adelman-McCarthy et al. 2006, ApJS, 162, 38; see also <a href="http://www.sdss.org/dr4/">http://www.sdss.org/dr4/</a> ) contains 800,000 spectra from 4783 square degrees. The authors have used automated techniques supplemented by visual classification to select 13,000 candidates. An extensive analysis of these objects has yielded 9316 white dwarfs, including 8000 DA, 713 DB, 41 DO or PG1159, 289 DC, 104 DQ, and 133 DZ types, as well as 928 hot subdwarf stars. As well as the 10,244 primary spectra, the authors have also presented 774 duplicate spectra of WD stars and 60 duplicate spectra of SD stars. Thus, the present table has 11,078 (=10,244 + 774 + 60) entries. 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 table was created by the HEASARC in February 2007 based on the merger of Table 1B and 1C obtained from the electronic ApJS website. 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:
- 28 Jun 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 .