- ID:
- ivo://nasa.heasarc/abell
- Title:
- Abell Clusters
- Short Name:
- Abell
- Date:
- 10 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The ABELL database contains information from a catalog of clusters of galaxies, each having at least 30 members within the magnitude range m3 to m3+2 (m3 is the magnitude of the third brightest cluster member) and each with a nominal redshift less than 0.2. The database contains the revised Northern Abell catalog, the Southern Abell catalog, and the Supplementary Southern Abell catalog; the catalogs are published as tables 3, 4 and 5 of Abell, Corwin & Orowin (1989). This database table was created by J. Osborne of Leicester from the STADAT SCAR file abelb.dat. The original SCAR version was created by Diana Parsons on 12 March 1990. This is a service provided by NASA HEASARC .
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- ID:
- ivo://nasa.heasarc/abellzcat
- Title:
- Abell Clusters Measured Redshifts Catalog
- Short Name:
- ABELLZCAT
- Date:
- 10 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The all-sky ACO (Abell, Corwin and Olowin 1989, ApJS, 70, 1) Catalog of 4073 rich clusters of galaxies and 1175 southern poor or distant S-clusters has been searched for published redshifts. Data for 1059 of them were found and classified into various quality classes, e.g. to reduce the problem of foreground contamination of redshifts. Taking the ACO selection criteria for redshifts, a total of 992 entries remain, 21 percent more than ACO. Redshifts for rich clusters are now virtually complete out to a redshift z of 0.05 in the north and of 0.04 in the south. In the north, the magnitude-redshift (m_10 - z) relation agrees with that of Kalinkov et al. (1985, Astr. Nachr., 306, 283). For the southern rich clusters, minor adjustments to the m_10 - z relation of ACO are suggested, while for the S-clusters the redshifts are about 30 percent lower than estimated. This table was created by the HEASARC in May 2010 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/VII/165A">CDS Catalog VII/165A</a> file catalog.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/qorgcat
- Title:
- All-Sky Optical Catalog of Radio/X-Ray Sources
- Short Name:
- QuasarOrg
- Date:
- 10 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The Quasars.org (QORG) Catalog is an all-sky optical catalog of radio/X-ray sources. The QORG Catalog aligns and overlays the year 2001/2 releases of the ROSAT HRI, RASS, PSPC and WGA X-ray catalogs, the NVSS (2002), FIRST (2003) and SUMSS (2003) radio catalogs, the Veron QSO catalog (2003) and various galaxy/star reference catalogs onto the optical APM and USNO-A catalogs. This catalog displays calculated percentage probabilities for each optical, radio/X-ray associated object of its likelihood of being a quasar, galaxy, star, or erroneous radio/X-ray association. This table contains the main Master QORG catalog (master.dat) and contains all 501,756 radio/X-ray associated optical objects and known quasars which are optically detected in APM/USNO-A. Up to six radio/X-ray catalog identifications are presented for each optical object, plus any double radio lobes (21,498 of these). These are superimposed (and laterally fitted) onto a 670,925,779-object optical background which combines APM and USNO-A data. Other subsets of this master catalog are available at the CDS, including the Free-Lunch catalog, a concise easy-to-read variant of the Master catalog showcasing just one X-ray and/or radio identification for each object, a subset catalog of QSO candidates, and a subset catalog of known QSOs/galaxies/stars. Objects presented in this catalog are those optical APM/USNO-A objects which are associated with X-ray/radio detections, or any optically-found catalogued QSO/AGN/Bl Lac objects, which have confidence levels >40% of being radio/X-ray emitting optical objects. There are 501,756 objects included in all (including 48,285 catalogued quasars), representing the 99.4% coverage of the sky which is available from the APM and USNO-A. Each object is shown as one entry giving the position in equatorial coordinates, red and blue optical magnitudes (recalibrated) and PSF class, calculated probabilities of the object being, separately, a quasar, galaxy, star, or erroneous radio/X-ray association, any radio identification from each of the NVSS, FIRST and SUMSS surveys, including candidate double-lobe detections, any X-ray identification from each of the ROSAT HRI, RASS, PSPC and WGA surveys, including fluxes and field shifts of those identifications, plus, if already catalogued, the object name and redshift where applicable. The QORG catalog and supporting data can be accessed from the catalog home page at <a href="http://quasars.org/qorg-data.htm">http://quasars.org/qorg-data.htm</a> Questions or comments on the catalog contents may be directed to the first author Eric Flesch at eric@flesch.org. The authors request that researchers using this catalog make a small acknowledgement of such use in any published papers which thereby result. This table was created by the HEASARC in November 2004 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/427/387">CDS Catalog J/A+A/427/387</a> file master.dat.gz. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/ascaegclus
- Title:
- ASCA Elliptical Galaxies and Galaxy Clusters Catalog
- Short Name:
- ASCAEGCLUS
- Date:
- 10 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- Utilizing ASCA archival data of about 300 objects - elliptical galaxies, groups, and clusters of galaxies - the authors performed systematic measurements of the X-ray properties of hot gas in their systems, and compiled them in this study. The steepness (power-law slope) of the luminosity-temperature (L-T) relation, L<sub>X</sub> ~ kT<sup>alpha</sup>, in the range of kT ~ 1.5 - 15 keV is alpha = 3.17 +/- 0.15, consistent with previous measurements. In the relation, the authors find two breaks at around intracluster medium (ICM) temperatures of 1 keV and 4 keV: alpha = 2.34 +/- 0.29 above 4 keV, 3.74 +/- 0.32 in the 1.5 to 5 keV range, and 4.03 +/- 1.07 below 1.5 keV. Two such breaks are also evident in the temperature and size relation. The steepness in the L-T relation at kT > 4 keV is consistent with the scale-relation derived from the CDM model, indicating that the gravitational effect is dominant in richer clusters, while poorer clusters suffer non-gravity effects. The steep L-T relation below 1 keV is mostly attributed to X-ray faint systems of elliptical galaxies and galaxy groups. The authors find that the ICM mass within the scaling radius R<sub>1500</sub> (the radius within which the averaged mass density is 1500 times higher than the critical density) follows the relation of M<sub>gas</sub> ~ T<sup>(2.33+/-0.07)</sup> from X-ray faint galaxies to rich clusters. Thus, the authors speculate that even such X-ray faint systems contain large-scale hot gas, which is too faint to detect. For this project, the authors utilized all of the ASCA data of elliptical galaxies and clusters of galaxies. Several clusters were observed more than once, and they chose the observation with the longest exposure. The total number of objects that the authors identified as elliptical galaxies and clusters was 313, and these are listed in this table. Some of the objects could not be utilized for deriving various correlations, due to either having an unknown redshift (17 objects), an insignificant detection (13 objects listed below), or contamination of the environmental X-ray emission, such as cluster emission around non-cD elliptical galaxies (10 objects: NGC 4472, NGC 4406, NGC 4374, NGC 1404, NGC 499, NGC 6034, NGC 2865, NGC 4291, CL 2236-04 and RX J1031.6-2607). Thus, the authors analyzed the ASCA data for 292 objects, among which were ~ 50 elliptical galaxies and galaxy groups. In this study, the authors assumed the Hubble constant to be 50 h<sub>50</sub> km s<sup>-1</sup> Mpc<sup>-1</sup> and q<sub>0</sub> to be 0. Table 1 of the reference paper (reproduced below) lists the 13 clusters for which only 90% confidence level upper limits to the flux in the observer's frame are available: <pre> Name Flux (0.5 - 2 keV) Upper Limit (erg/s/cm<sup>2</sup>) NGC 5018 9.8 x 10<sup>14</sup> GHO 1322+3114 1.3 x 10<sup>13</sup> J1888.16CL 5.9 x 10<sup>14</sup> CL 0317+1521 4.5 x 10<sup>14</sup> MS 1512.4+3647 1.0 x 10<sup>12</sup> PRG 38 6.9 x 10<sup>14</sup> SCGG 205 6.9 x 10<sup>14</sup> RGH 101 9.1 x 10<sup>14</sup> 3C 184 8.5 x 10<sup>14</sup> RX J1756.5+6512 1.6 x 10<sup>13</sup> 3C 324 5.4 x 10<sup>14</sup> PDCS 01 2.8 x 10<sup>14</sup> MS 0147.8-3941 5.0 x 10<sup>14</sup> </pre> This table was created by the HEASARC in December 2011 based on CDA Catalog J/PASJ/56/965 files table3.dat, table4.dat, table5.dat, table6.dat and table7.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/arxa
- Title:
- Atlas of Radio/X-Ray Associations (ARXA)
- Short Name:
- ARXA
- Date:
- 10 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The Atlas of Radio/X-Ray Associations (ARXA) is a compendium of all cataloged or APM/USNO-A optical objects which are found to be associated with XMM-Newton, Chandra, RASS, HRI, PSPC or WGACAT X-ray detections, or with NVSS, FIRST or SUMSS radio detections. All detections are listed, plus double radio lobes where found. The source number counts are: <pre> Optical objects - 602,570. NVSS - 266,148 core associations, plus 8309 double lobes. FIRST - 173,383 core associations, plus 12,844 double lobes. SUMSS - 59,138 core associations, plus 2529 double lobes. XMM associations - 57,778. Chandra associations - 32,951. ROSAT RASS - 47,486. ROSAT HRI - 15,523. ROSAT PSPC - 35,607. WGA - 24,226. </pre> Each optical object is given as one entry in this catalog, containing the sky coordinates, the object name (from the literature where available), APM and USNO-A sourced red and blue photometry, redshift, the source catalogs for the name and redshift, the calculated odds that the object is a quasar, galaxy, star, or erroneous association, and the radio & X-ray identifiers, up to 10 of them possible although usually just 1 or 2. This catalog supersedes the previous similar compilation by the same author, the Quasars.org (QORG) Catalog, called QORGCAT in the HEASARC's Browse (see <a href="http://quasars.org/qorg-data.htm">http://quasars.org/qorg-data.htm</a>). Questions or comments on ARXA may be directed to eric@flesch.org. See also: <pre> APM home page <a href="http://www.ast.cam.ac.uk/~apmcat">http://www.ast.cam.ac.uk/~apmcat</a> USNO-A home page <a href="http://www.nofs.navy.mil/">http://www.nofs.navy.mil/</a> NVSS home page <a href="http://www.cv.nrao.edu/nvss/">http://www.cv.nrao.edu/nvss/</a> FIRST home page <a href="http://sundog.stsci.edu/">http://sundog.stsci.edu/</a> SUMSS home page <a href="http://www.astrop.physics.usyd.edu.au/SUMSS/index.html">http://www.astrop.physics.usyd.edu.au/SUMSS/index.html</a> XMM-Newton home page <a href="http://xmmssc-www.star.le.ac.uk">http://xmmssc-www.star.le.ac.uk</a> HRI & PSPC home page <a href="http://www.mpe.mpg.de/ROSAT/">http://www.mpe.mpg.de/ROSAT/</a> WGA home page <a href="http://wgacat.gsfc.nasa.gov/wgacat/wgacat.html">http://wgacat.gsfc.nasa.gov/wgacat/wgacat.html</a> RASS-FSC home page <a href="http://www.xray.mpe.mpg.de/rosat/survey/rass-fsc">http://www.xray.mpe.mpg.de/rosat/survey/rass-fsc</a> RASS-BSC home page <a href="http://www.xray.mpe.mpg.de/rosat/survey/rass-bsc">http://www.xray.mpe.mpg.de/rosat/survey/rass-bsc</a> Chandra home page <a href="http://chandra.harvard.edu">http://chandra.harvard.edu</a> XAssist home page <a href="http://xassist.pha.jhu.edu/zope/xassist">http://xassist.pha.jhu.edu/zope/xassist</a> (XMMX & CXOX sources are from XAssist) </pre> If using this catalog in published research, please add a small mention in the acknowledgements. This table is based on research which made use of the NASA/IPAC Extragalactic Database (NED) operated by the Jet Propulsion Laboratory, California Institute of Technology, under contract with NASA. This online catalog was created by the HEASARC in January 2010 based on a machine-readable table obtained from the author's ARXA web site at <a href="http://quasars.org/arxa.htm">http://quasars.org/arxa.htm</a>. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/baxgalclus
- Title:
- BAX X-Ray Galaxy Clusters and Groups Catalog
- Short Name:
- BAXGalClus
- Date:
- 10 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains the BAX X-Ray Galaxy Clusters and Groups Catalog. BAX (`Base de Donnees Amas de Galaxies X': see <a href="http://bax.ast.obs-mip.fr/">http://bax.ast.obs-mip.fr/</a> for more details) is a multi-wavelength database dedicated to X-ray clusters and groups of galaxies which allows detailed information retrieval. BAX is designed to support astronomical research by providing access to published measurements of the main physical quantities and to the related bibliographic references: basic data stored in the database are cluster/group identifiers, equatorial coordinates, redshift, flux, X-ray luminosity (in the ROSAT band) and temperature, and (in the online version at <a href="http://bax.ast.obs-mip.fr/">http://bax.ast.obs-mip.fr/</a>) links to additional linked parameters (in X-rays, such as spatial profile parameters, as well as SZ parameters of the hot gas, lensing measurements, and data at other wavelengths, such as the optical and radio bands). The clusters and groups in the online BAX database can be queried by the basic parameters as well as the linked parameters or combinations of these. The authors expect BAX to become an important tool for the astronomical community. BAX will optimize various aspects of the scientific analysis of X-ray clusters and groups of galaxies, from proposal planning to data collection, interpretation and publication, from both ground based facilities like MEGACAM (CFHT), VIRMOS (VLT) and from space missions like XMM-Newton, Chandra and Planck. This table was created by the HEASARC in October 2004 based on CDS table B/bax/bax.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/cgmw
- Title:
- Candidate Galaxies Behind the Milky Way
- Short Name:
- CG
- Date:
- 10 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This catalog gathers the searches for galaxies of apparent size greater than 0.1 mm on film (6.7" in angular size) lieing behind the Milky Way from photographic surveys in the near-infrared. The four volumes (CGMW1, CGMW2, CGMW3, and CGMW4) cover the galactic longitude ranges from -7 to +43 degrees, and from 210 to 250 degrees. The two volumes, CGMW1 and CGMW2, giving about 7000 galaxies behind the Milky Way between l = 210 degrees and 250 degrees, represent a systematic search for galaxies by means of 32 film copies of the UK Schmidt Southern Infrared Atlas on the Milky Way covering about 900 square degrees. In the search galaxies with apparent sizes greater than 0.1mm on film (6.7 arcsec in size) were detected by visual inspection. The material and procedure of search are described as well as the detectability of galaxies in paper I and paper II appended before Vol. 1 and Vol. 2 of the catalog, respectively, which have been published in Publ. Astron. Soc Japan, Vol. 42 (1990) and Vol. 43 (1991). The parameters of catalogued galaxies are also explained in paper I. Cross-identifications with other catalogs are also given. The third volume CGMW3 lists about 5300 galaxy candidates having sizes larger than 0.1 arcminutes that were found in a search of Schmidt atlases covering a Milky Way region of about 800 square degrees around l = 8 to 43 degrees, and b = -17 to +17 degrees. This surveyed region is located between the northern Local void and the Ophiuchus void. The fourth volume CGMW4 lists about 7150 galaxies and galaxy candidates having sizes larger than 0.1 arcminutes that were found in a search of Schmidt atlases covering a Milky Way region of about 260 square degrees around l = -7 to +16 degrees, and b = -19 to -1 degrees, i.e., a field in Sagittarius in the Galactic Center region. This database was created by the HEASARC in October 1999 based on a machine-readable version that was obtained from the CDS Data Center. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/zcat
- Title:
- CfA Redshift Catalog (June 1995 Version)
- Short Name:
- CFAZ
- Date:
- 10 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The ZCAT database contains the CfA Redshift Catalog, which incorporates much of the latest velocity data from the Whipple Observatory and other sources, as well as velocities from earlier compilations such as the "Second Reference Catalog" of de Vaucouleurs, de Vaucouleurs, and Corwin; the "Index of Galaxy Spectra" of Gisler and Friel; and the "Catalog of Radial Velocities of Galaxies" of Palumbo, Tanzella-Nitti, and Vettolani. It includes BT magnitudes, some UGC numbers, and increased "accuracy" in the velocity source information. The data presented here have primarily been assembled for the purpose of studying the large scale structure of the universe, and, as such, are nearly complete in redshift information, but are not necessarily complete in such categories as diameter, magnitude, and cross-references to other catalogues. The original HEASARC version was constructed based on an earlier version of the catalog and was released on November 15, 1996. The HEASARC created the current version of ZCAT in February 2001 based on CDS/ADC Catalog VII/193, "The CfA Redshift Catalogue", Version June 1995, tables <a href="https://cdsarc.cds.unistra.fr/ftp/cats/VII/193/zcat.dat">https://cdsarc.cds.unistra.fr/ftp/cats/VII/193/zcat.dat</a> and zbig.dat. The former table contains the main body of the CFA Redshift Catalog (57536 objects) and entries from it are distinguishable in the current database by having either listed radial velocity values but not redshifts or neither, while the latter table contains 1202 high-redshift galaxies (distinguishable in the current database by their having listed redshift values but not radial velocities). This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/cfa2s
- Title:
- CfA Redshift Survey: South Galactic Cap Data
- Short Name:
- CfARed.S.
- Date:
- 10 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The Center for Astrophysics (CfA) Redshift Survey South Galactic Cap (CFA2S) Catalog contains redshifts for a sample of about 4300 galaxies with blue (Zwicky B(0) type) magnitude <= 15.5 covering the range from 20 h to 4h in right ascension and from -2.5 deg to 90 deg in declination. This sample is complete for all galaxies in the merge of the Zwicky et al. and Nilson catalogs in the south Galactic cap. Redshifts for 2964 of these were measured as part of the second CfA Redshift Survey. The data reveal large voids in the foreground and background of the Perseus-Pisces Supercluster. The largest of these voids lies at a mean velocity ~ 8000km/s, has diameter of ~ 5000km/s, and is enclosed by a complex of dense structures. The large structure known as the Perseus-Pisces Supercluster forms the near side of this complex. On the far side of this large void, at a mean velocity of ~ 12000km/s, there is another coherent dense wall. The structures in this survey support the view that galaxies generally lie on surfaces surrounding or nearly surrounding low-density regions or voids. This table was created by the HEASARC in March 2005 based on CDS table J/ApJS/121/287/cfa2s.dat.gz This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/ccosrssfag
- Title:
- Chandra COSMOS Radio-Selected Star-Forming Galaxies and AGN Catalog
- Short Name:
- CCOSRSSFAG
- Date:
- 10 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- X-ray surveys contain sizable numbers of star-forming galaxies, beyond the AGN which usually make up the majority of detections. Many methods to separate the two populations are used in the literature, based on X-ray and multi-wavelength properties. The authors aim at a detailed test of the classification schemes and to study the X-ray properties of the resulting samples. They build on a sample of galaxies selected at 1.4 GHz in the VLA-COSMOS survey, classified by Smolcic et al. (2008, ApJS, 177, 14) according to their optical colors and also observed by Chandra. A similarly selected control sample of AGN is also used for comparison. The authors review some X-ray based classification criteria and check how they affect the sample composition. The efficiency of the classification scheme devised by Smolcic et al. (2008) is such that ~30% of composite/misclassified objects are expected because of the higher X-ray brightness of AGN with respect to galaxies. The latter fraction is actually 50% in the X-ray detected sources, while it is expected to be much lower among X-ray undetected sources. Indeed, the analysis of the stacked spectrum of undetected sources shows, consistently, strongly different properties between the AGN and galaxy samples. X-ray based selection criteria are then used to refine both samples. The radio/X-ray luminosity correlation for star-forming (SF) galaxies is found to hold with the same X-ray/radio ratio valid for nearby galaxies. Some evolution of the ratio may be possible for sources at high redshift or high luminosity, though it is likely explained by a bias arising from the radio selection. Finally, in their paper the authors discuss the X-ray number counts of star-forming galaxies from the VLA- and C-COSMOS surveys according to different selection criteria, and compare them to the similar determination from the Chandra Deep Fields. The classification scheme proposed here may find application in future works and surveys. This table contains the catalogs of radio-selected SF- and AGN-candidate sources with an X-ray detection in C-COSMOS which were contained in Tables 2 and 3 of the reference paper, respectively. The HEASARC has merged these into a single table, adding a new parameter sample which is set to 'SFG' for radio-selected SF-candidate sources from Table 2 and to 'AGN' for the AGN-candidate sources from Table 3. This table was created by the HEASARC in June 2012 based on CDS table J/A+A/542/A16 files table2.dat and table3.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/cosmosvlba
- Title:
- COSMOS Field VLBA Observations 1.4-GHz Source Catalog
- Short Name:
- COSMOSVLBA
- Date:
- 10 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains the results of a project using wide-field Very Long Baseline Interferometry (VLBI) observations at 1.4 GHz of 2,865 known radio sources in the Cosmic Evolution Survey (COSMOS) field, a field which has exceptional multi-wavelength coverage. The main objective of this study is to identify the active galactic nuclei (AGN) in this field. Wide-field VLBI observations were made of all known radio sources in the COSMOS field at 1.4 GHz using the Very Long Baseline Array (VLBA). The authors also collected complementary multiwavelength information from the literature for the VLBA-detected sources.The combination of the number of sources, sensitivity, angular resolution and the area covered by this project are unprecedented. A catalog which contains the VLBI-detected sources is presented, the main purpose of which is to be used as an AGN catalog. the complementary multiwavelength (optical, infrared and X-ray) information of the VLBI-detected sources is also presented. The authors have detected 468 radio sources, expected to be AGN, with the VLBA. This is, to date, the largest sample assembled of VLBI-detected sources in the sub-mJy regime. They find a detection fraction of 20% +/- 1%, considering only those sources from the input catalog which were in principle detectable with the VLBA (2,361). As a function of the VLA flux density, the detection fraction is higher for higher flux densities, since at high flux densities a source could be detected even if the VLBI core accounts for a small percentage of the total flux density. As a function of redshift, the authors see no evolution of the detection fraction over the redshift range 0.5 < z < 3. In addition, they find that faint radio sources typically have a greater fraction of their radio luminosity in a compact core: ~70% of the sub-mJy sources detected with the VLBA have more than half of their total radio luminosity in a VLBI-scale component, whereas this is true for only ~30% of the sources that are brighter than 10 mJy. This suggests that fainter radio sources differ intrinsically from brighter ones. Across the entire sample, the authors find the predominant morphological classification of the host galaxies of the VLBA-detected sources to be early type (57%), although this varies with redshift and at z > 1.5 they find that spiral galaxies become the most prevalent (48%). The number of detections is high enough to study the faint radio population with statistically significant numbers. The authors demonstrate that wide-field VLBI observations, together with new calibration methods such as multi-source self-calibration and mosaicking, result in information which is difficult or impossible to obtain otherwise. This table contains 504 entries, including the 468 VLBA-detected sources and, for sources with multiple components, entries for the individual components. Among the detected sources, there are 452 single, 13 double, 2 triple and 1 quadruple source. Source entries have no suffix in their vlba_source_id, e.g., 'C3293', whereas component entries have a, b, c or d suffixes, e.g., 'C0090a' (and a value of 2 for the multi_cpt_flag parameter). This table was created by the HEASARC in December 2017 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/607/A132">CDS Catalog J/A+A/607/A132</a> files vlba_cat.dat and vlba_mw.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/sixdfgs
- Title:
- 6dFGS Galaxy Survey Final Redshift Release Catalog
- Short Name:
- SIXDFGS
- Date:
- 10 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The final redshift release of the 6dF Galaxy Survey (6dFGS) is a combined redshift and peculiar velocity survey over the southern sky (|b| > 10 degrees). Its 136,304 spectra have yielded 110,256 new extragalactic redshifts and a new catalogue of 125,071 galaxies making near-complete samples with limits in (K, H, J, r<sub>F</sub>, b<sub>J</sub>) (12.65, 12.95, 13.75, 15.60, 16.75). The median redshift of the survey is 0.053. The catalog includes basic data for the galaxies in the 6dFGS with redshifts, using the best 6dFGS redshifts (radial velocity quality flag Q =3 or 4) plus available redshifts from SDSS, 2dFGRS and ZCAT (124,647 entries in all). It supersedes the previous DR2 version (CDS Cat. VII/249). The home page of of the 6dFGS database is <a href="http://www-wfau.roe.ac.uk/6dFGS">http://www-wfau.roe.ac.uk/6dFGS</a>. Any use of these data should explicitly state that they come from the Final Release of 6dFGS and cite both the 6dGS DR3 paper (Jones et al. 2009, MNRAS, 399, 683) as well as the original 6dFGS survey paper (Jones et al. 2004, MNRAS, 355, 747). This table was created by the HEASARC in March 2011 based on CDS Catalog VII/259 file 6dfgs.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/twodfqsoz
- Title:
- 2dF QSO Redshift (2QZ) Survey
- Short Name:
- TWODFQSOZ
- Date:
- 10 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The final catalog of the 2dF QSO Redshift Survey (2QZ) is based on Anglo-Australian Telescope 2dF spectroscopic observations of 44,576 color-selected (u, b<sub>J</sub>, r) objects with 18.25 < b<sub>J</sub> < 20.85 selected from automated plate measurement scans of UK Schmidt Telescope (UKST) photographic plates. The 2QZ comprises 23,338 quasi-stellar objects (QSOs), 12,292 galactic stars (including 2,071 white dwarfs) and 4,558 compact narrow emission-line galaxies. The authors obtained a reliable spectroscopic identification for 86 per cent of objects observed with 2dF. They also report on the 6dF QSO Redshift Survey (6QZ), based on UKST 6dF observations of 1,564 brighter (16 < b<sub>J</sub> < 18.25) sources selected from the same photographic input catalog. In total, the authors identified 322 QSOs spectroscopically in the 6QZ. The completed 2QZ is, by more than a factor of 50, the largest homogeneous QSO catalog ever constructed at these faint limits (b<sub>J</sub> < 20.85) and high QSO surface densities (35 QSOs/deg<sup>2</sup>). As such, it represents an important resource in the study of the Universe at moderate-to-high redshifts. The survey area comprised 30 UKST fields, arranged in two 75 degrees by 5 degrees declination strips, one passing across the South Galactic Gap centered on Dec = -30 degrees (the SGP strip), and the other across the North Galactic Gap centered on Dec = 0 degrees (referred to in the reference paper as the equatorial strip, but also known as the NGP strip. The total survey area is 721.6 deg<sup>2</sup>, when allowance is made for regions of sky excised around bright stars. Spectroscopic observations of the input catalogue were made with the 2dF instrument at the Anglo-Australian Telescope (AAT; the 2QZ sample) and the 6dF instrument at the UKST (the 6QZ sample). 2dF spectroscopic observations began in January 1997 and were completed in April 2002. Six-degree Field observations were performed over the period 2001 March-2002 September. This online catalog was created by the HEASARC in October 2010 based on the machine-readable table 2qz.dat obtained from the CDS (their catalog VII/241). This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/eingalclus
- Title:
- Einstein Observatory Clusters of Galaxies Catalog
- Short Name:
- Einstein/Clus
- Date:
- 10 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The Einstein Observatory Clusters of Galaxies Catalog presents the X-ray characteristics of a sample of 368 clusters of galaxies with redshifts less than 0.2 which were observed with the Einstein Imaging Proportional Counter (IPC). For each cluster, the authors measured the 0.5 - 4.5 keV counting rate and computed the 0.5 - 4.5 keV source luminosity, as well as the bolometric luminosity within fixed metric radii. They detected 85% of Abell clusters with z < 0.1, demonstrating that the large majority of these optically selected clusters are not the results of chance superpositions. For 163 clusters, they measured their X-ray surface brightness profiles and determined their core radii. For about 230 clusters, they then used either their measured core radii and beta values, or mean values derived for this sample, to measure central gas densities and gas masses. They used estimated or measured cluster gas temperatures, along with the derived gas-density profiles, to estimate total cluster masses, under the assumptions that the gas is isothermal and in hydrostatic equilibrium. This table was created by the HEASARC in June 2005 based on the merger of CDS tables J/ApJ/511/65/table3.dat and table4.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/esouppsala
- Title:
- ESO-Uppsala ESO(B) Survey
- Short Name:
- ESO/Uppsala
- Date:
- 10 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This database table was derived from information provided in "The ESO/Uppsala Survey of the ESO(B) Atlas" (ESO/U), which is a joint project undertaken by the European Southern Observatory (ESO) and the Uppsala Observatory to provide a systematic and homogeneous search of the ESO(B) Atlas (also known as the Quick Blue Survey). The ESO(B) Atlas, taken with the ESO 1 m Schmidt telescope at La Silla, Chile, covers 606 fields from -90 to -20 degrees of declination. The fields are similar in size and scale to those of the Palomar Observatory Sky Survey. Unsensitized IIa-O plates and a 2 mm GG385 filter were used to give a passband similar to the Johnson B color. Additional information is available from the HEASARC. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/fsvsclustr
- Title:
- Faint Sky Variability Survey Catalog of Galaxy Clusters and Rich Groups
- Short Name:
- FSVSClusGR
- Date:
- 10 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The Faint Sky Variability Survey Catalog of Galaxy Clusters and Rich Groups contains a a large sample of 598 galaxy clusters and rich groups discovered in the data of the Faint Sky Variability Survey (FSVS). The clusters have been identified using a fully automated, semi-parametric technique based on a maximum likelihood approach applied to Voronoi tessellation, and enhanced by color discrimination. The sample covers a wide range of richness, has a density of ~28 clusters per square degree, and spans a range of estimated redshifts of 0.05 < z < 0.9 with mean <z> = 0.345. Assuming the presence of a cluster red sequence, the uncertainty of the estimated cluster redshifts is assessed to be sigma ~ 0.03. Containing over 100 clusters with z > 0.6, the catalog contributes substantially to the current total of optically-selected, intermediate-redshift clusters, and complements the existing, usually X-ray selected, samples. The FSVS fields are accessible for observation throughout the whole year, making them particularly suited for large follow-up programs. The construction of this FSVS Cluster Catalogue completes a fundamental component of the authors' continuing program to investigate the environments of quasars and the chemical evolution of galaxies. The present table contains the list of all clusters with their basic parameters. This table was created by the HEASARC in July 2006 based on the table cluster_catalogue.txt copied from the first author's website <a href="https://web.archive.org/web/20100318044103/www-astro.physics.ox.ac.uk/~iks/FSVScatalogue/">https://web.archive.org/web/20100318044103/www-astro.physics.ox.ac.uk/~iks/FSVScatalogue/</a> (no longer available, unfortunately). Refer instead to <a href="https://cdsarc.unistra.fr/viz-bin/cat/J/MNRAS/369/1334">https://cdsarc.unistra.fr/viz-bin/cat/J/MNRAS/369/1334</a> for the data files and to <a href="https://www.noao.edu/survey-archives/fsvs/">https://www.noao.edu/survey-archives/fsvs/</a> for additional information about the survey. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/markarian
- Title:
- First Byurakan Survey (Markarian) Catalog of UV-Excess Galaxies
- Short Name:
- Markarian
- Date:
- 10 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- A catalog of galaxies with UV-continuum (Markarian galaxies) detected during the First Byurakan Survey (FBS) is presented. The purpose of the FBS was to search for peculiar faint extragalactic objects with UV-excess radiation and to study them. The procedure of observations and processing, the FBS areas, the object selection and classification criteria and also several selection effects are described in the reference. The catalog contains the following initial data on all the objects: the precise coordinates, visual magnitudes, angular sizes, redshifts and classification types. The observational results of slit spectra, UBV-photometry, IR-photometry (IRAS data), morphology and some other data are also included in the catalog. While compiling the catalog, the authors introduced some necessary corrections in the data of the earlier published lists on galaxies with UV-continuum excesses. In addition, the authors included the objects with numbers 1501-1515. In most cases, they are well-known Seyfert galaxies omitted by the authors in the lists, but detected on the plates. 48 objects from their lists are not included in the catalog, since they are either stars of our Galaxy or star projections on the galaxies. This catalog presents the largest homogeneous sample of AGN of different types on the northern sky for bright objects (apparent magnitude < 16.0). Up to the middle of 1987 redshifts were measured for 1459 out of 1469 objects in the catalog. This table was created by the HEASARC in November 2009 based on the electronic version of the First Byurakan Survey (Markarian galaxies catalog) which was obtained from the CDS (their catalog VII/172 file table7.dat). It replaced an earlier version of the 'Markarian Catalog' which was based on the original galaxy lists of Markarian et al. (<a href="https://cdsarc.cds.unistra.fr/ftp/cats/VII/61A">CDS catalog VII/61A</a>). This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/denisigal
- Title:
- First DENIS I-band Extragalactic Catalog
- Short Name:
- DENIS/I
- Date:
- 10 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This database contains the release of the provisional extragalactic catalog constructed from the "Deep Near Infrared Southern Sky Survey" (DENIS) and is sometimes referred to as REDCAT (Rapid Extraction from DENIS Catalog). It was created using an automatic galaxy recognition program based on a discriminating analysis, the efficiency of which is estimated to be better than 99%. The nominal accuracy for galaxy coordinates calculated with the Guide Star Catalog is about 6 arcseconds. The cross-identification with galaxies available in the Lyon-Meudon Extragalactic DAtabase (LEDA) allows a calibration of the I-band photometry with the sample of Mathewson et al. (1992, ApJS, 81, 413) and Mathewson and Ford (1996, ApJS, 107, 97). Thus, the catalog contains total I-band magnitude, isophotal diameter, axis ratio, position angle and a rough estimate of the morphological type code for 20620 galaxies. The internal completeness of this catalog reaches a limiting I-band magnitude of 14.5, with a photometric accuracy of 0.18 mag. 25% of the Southern sky has been processed in this study. This database was created by the HEASARC in July 1999 based on a machine-readable version that was obtained form the CDS Data Center. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/glxsdssqs2
- Title:
- GALEX/SDSS z=0.5-1.5 QSO Candidates Catalog
- Short Name:
- GLXSDSSQS2
- Date:
- 10 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- A sample of ~60,000 objects from the combined Sloan Digital Sky Survey-Galaxy Evolution Explorer (SDSS-GALEX) database with UV-optical colors that should isolate QSOs in the redshift range 0.5 to 1.5 is discussed. The authors use SDSS spectra of a subsample of ~ 4,500 to remove stellar and galaxy contaminants in the sample to a very high level, based on the 7-band photometry. In their paper, they discuss the distributions of redshift, luminosity, and reddening of the 19,100 QSOs (~96%) that they estimate to be present in their final sample of 19,812 point sources. This latter catalog is available in the present table. This paper is based on archival data from the Galaxy Evolution Explorer (GALEX) which is operated for NASA by the California Institute of Technology under NASA contract NAS5-98034, and on data from the SDSS. This table was created by the HEASARC in March 2011 based on the electronic version of Table 2 from the reference paper which was obtained from the AJ web site. Some of the values for the name parameter in the HEASARC's implementation of this table were corrected in April 2018. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/gcscat
- Title:
- Globular Cluster Systems of Galaxies Catalog
- Short Name:
- GCSCAT
- Date:
- 10 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains a catalog of 422 galaxies with published measurements of their globular cluster (GC) populations. Of these, 248 are E galaxies, 93 are S0 galaxies, and 81 are spirals or irregulars. Among various correlations of the total number of GCs with other global galaxy properties, the authors find that the number of globular clusters N<sub>GC</sub> correlates well though nonlinearly with the dynamical mass of the galaxy bulge M<sub>dyn</sub> = 4 sigma _e_<sup>2</sup> R<sub>e</sub>/G, where sigma<sub>e</sub> is the central velocity dispersion and R<sub>e</sub> the effective radius of the galaxy light profile. In their paper, the authors also present updated versions of the GC specific frequency S<sub>N</sub> and specific mass S<sub>M</sub> versus host galaxy luminosity and baryonic mass. These graphs exhibit the previously known U-shape: highest S<sub>N</sub> or S<sub>M</sub> values occur for either dwarfs or supergiants, but in the mid-range of galaxy size (10<sup>9</sup> - 10<sup>10</sup> L<sub>sun</sub>) the GC numbers fall along a well-defined baseline value of S<sub>N</sub> ~= 1 or S<sub>M</sub> = 0.1, similar among all galaxy types. Along with other recent discussions, the authors suggest that this trend may represent the effects of feedback, which systematically inhibited early star formation at either very low or very high galaxy mass, but which had its minimum effect for intermediate masses. Their results strongly reinforce recent proposals that GC formation efficiency appears to be most nearly proportional to the galaxy halo mass M<sub>halo</sub>. The mean "absolute" efficiency ratio for GC formation that the authors derive from the catalog data is M<sub>GCS</sub>/M<sub>halo</sub> = 6 x 10<sup>-5</sup>. They suggest that the galaxy-to-galaxy scatter around this mean value may arise in part because of differences in the relative timing of GC formation versus field-star formation. Finally, they find that an excellent empirical predictor of total GC population for galaxies of all luminosities is N<sub>GC</sub> ~ (R<sub>e</sub> sigma<sub>e</sub>)<sup>1.3</sup>, a result consistent with fundamental plane scaling relations. This table was created by the HEASARC in February 2014 based on an electronic version of Table 1 from the reference paper which was obtained from the ApJ web site. A duplicate entry for NGC 4417 was removed in June 2019. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/a2pic
- Title:
- HEAO 1 A2 Piccinotti Catalog
- Short Name:
- A2PIC
- Date:
- 10 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The HEAO 1 A-2 experiment's operations began on day 224 of 1977 (12 August 1977) and ended on day 739 of 1977 (9 January 1979). The A-2 experiment performed two independent, low-background, high-sensitivity surveys of the entire sky 6 months apart, the first scan during days 248 to 437 of 1977 (5 September 1977 - 13 March 1978) and the second scan during days 73 to 254 of 1978 (14 March 1978 - 11 September 1978). The authors analyzed the A-2 data in order to obtain a complete flux-limited sample of extragalactic X-ray sources. The region between galactic latitudes of -20 and +20 degrees was excluded to minimize contamination from galactic sources. A circle of 6 degrees radius around the Large Magellanic Cloud sources was also excluded to prevent confusion problems. Therefore, there remained 65.5% of the sky (8.23 steradians) covered by this survey. The lowest statistical significance for the existence of the sources included in this catalog is 5 sigma, as required by the maximum likelihood methods used by the authors to determine the log N - log S parameters. Taking into account this statistical significance requirement, the authors estimated the completeness level of the first and second scans to be 1.25 and 1.8 R15 ct/s, respectively. 1 R15 ct/s is approximately 2.17 x 10<sup>-11</sup> erg/cm<sup>2</sup>/s in the 2-10 keV energy band for a power-law spectrum with a photon index of 1.65. This catalog contains data for 68 non-galactic sources (61 extragalactic and 7 unidentified sources) which were listed in Table 1 of the published catalog. The identified sources fall into several categories, including narrow emission line galaxies, broad emission line galaxies, BL Lacertae objects, and clusters of galaxies. This table was last revised by the HEASARC in November 2004 when 2 sources (H1257-042 and H1325-020) which had for some reason been omitted from the previous HEASARC version (the provenance of which is somewhat uncertain) were added back in to the table. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/exgalemobj
- Title:
- Hewitt&Burbidge(1991)CatalogofExtragalacticEmission-LineObjects
- Short Name:
- H&B91
- Date:
- 10 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This is the Hewitt & Burbidge (1991) Optical Catalog of Extragalactic Emission-Line Objects Similar to Quasi-Stellar Objects. It contains a total of 935 galaxies which have optical properties similar to QSOs. Most of the objects appear to be nonstellar. The majority, more than 700, have redshifts z that are <= 0.2, and most have been classified as Seyfert galaxies, N systems, or radio galaxies. The redshift distribution peaks at z ~ 0.025, but there are about 200 powerful radio galaxies in the extended tail of the distribution which have z > 0.2. There is a separate and distinct peak in the redshift distribution at z = 0.06. Notice that this catalog does not include star-like objects with emission-line redshifts >= 0.1 (these can be found in the HEASARC QSO database which contains the Revised and Updated Catalog of Quasi-Stellar Objects" of Hewitt, A. and Burbidge, G. 1993, ApJS, Vol. 87, pp. 451-947). Neither does it contain LINERs (sometimes called Seyfert 3 galaxies) or starburst galaxies. This database was created by the HEASARC in February 2001 based on CDS/ADC Catalog VII/178 (table1.dat). This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/qso
- Title:
- Hewitt&Burbidge(1993)QSOCatalog
- Short Name:
- HB
- Date:
- 10 May 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/hcg
- Title:
- Hickson Compact Groups of Galaxies (HCG) Catalog
- Short Name:
- Hickson Group
- Date:
- 10 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The HCG database table is based on the Hickson Catalog, which is a list of 100 compact groups of galaxies that were identified by a systematic search of the Palomar Observatory Sky Survey red prints. Each group contains four or more galaxies, has an estimated mean surface brightness brighter than 26.0 magnitude per arcsec^2 and satisfies an isolation criterion. Dynamical parameters which were derived for 92 of the 100 groups are also included in the database. (Note that the Hubble constant was assumed to be Ho = 100 km/s/Mpc.) This database table essentially contains the information given in Table 1 of Hickson, P. (1982, ApJ, 255, 382) and Table 3 of Hickson, P. et al. (1992, ApJ, 399, 353). Consequently, the information on individual galaxies in the Hickson groups that is also given in these references, e.g., in Table 2 of Hickson, P. et al. (1992, ApJ, 399, 353), is not in the HCG database table; however, the latter data can be found in the related HEASARC database table HCGGALAXY. This online catalog was created by the HEASARC in August, 1999, based on machine-readable tables obtained from the ADC/CDS data centers (CDS catalog VII/213: files groups.dat and dynamics.dat). The HEASARC refined the coordinates, corrected the dynamics_flag values, and updated the table's metadata in August, 2005. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/hcggalaxy
- Title:
- Hickson Compact Groups of Galaxies (HCG) Individual Galaxies Data
- Short Name:
- Hickson(Gal)
- Date:
- 10 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The HCGGALAXY database table is based on the Hickson Catalog of Compact Groups, and contains data on 463 galaxies in 100 compact groups of galaxies that were identified by a systematic search of the Palomar Observatory Sky Survey red prints. Each group contains four or more galaxies, has an estimated mean surface brightness brighter than 26.0 magnitude per arcsec^2 and satisfies an isolation criterion. Astrometry, photometry, and morphological types, derived from CCD images, are presented for the 463 galaxies. Radial velocities are given for 457 of the 463 galaxies: more than 84% of the galaxies measured have radial velocities that are within 1000 km/s of the group median velocity. Morphological information derived from either an isophotal analysis or from a visual inspection of images is given for 210 of the 463 galaxies. This database table essentially contains the information given in Table 2 of Hickson, P. et al. (1989, ApJS, 70, 687), Table 2 of Hickson, P. et al. (1992, ApJ, 399, 353), and Table 2 of Mendes de Oliveira, C. and Hickson, P. (1994, ApJ, 427, 684). Consequently, the information on the properties of the Hickson Compact Groups as units that is also given in some of these references, e.g., in Table 3 of Hickson, P. et al. (1992, ApJ, 399, 353), is not in the HCGGALXY database table; however, the latter data can be found in the related HEASARC database table HCG. This database table was created by the HEASARC in August, 1999, based on machine-readable tables obtained from the ADC/CDS data centers (CDS catalog VII/213, files galaxies.dat and morpho.dat). The HEASARC added Galactic coordinates and updated the table's metadata in August, 2005. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/iraspscz
- Title:
- IRAS Point Source Catalog Redshift (PSCz) Catalog
- Short Name:
- IRASPSCZ
- Date:
- 10 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The IRAS Point Source Catalog Redshift (PSCz) Survey consists of redshifts, infrared and optical photometry, and assorted other information for 18351 IRAS sources, mostly selected from the Point Source Catalog. The survey was designed to select almost all galaxies with flux brighter than 0.595 Jy at 60 microns (µm), over the 84% of the sky with extinction small enough that reliable and complete optical identification and spectroscopy was possible. Some of the sources are not galaxies and some are multiple entries for the same galaxy as described in the reference paper. There are in total 15,411 galaxies or possible galaxies, for which redshifts are available for 14,677. The galaxies without redshift are mostly distant or at low latitude, as described in the paper. Many of these galaxies have now been observed as part of the BTP project (Saunders et al 1999, astro-ph/9909174 "The Behind the Plane Survey"), and their redshifts were to be included in future revisions of this catalog. The full catalog for the PSCz Catalog contains more than 120 parameters and is available at the CDS in the directory <a href="http://cdsarc.u-strasbg.fr/ftp/cats/VII/221/">http://cdsarc.u-strasbg.fr/ftp/cats/VII/221/</a> as the files pscz.dat (18,351 sources in the main catalog) and psczcg.dat (60 additional sources close to the coverage gap). There is also a 'short' version of the catalog, psczvs.dat and psczcgvs.dat, containing 19 parameters, sufficient information for most studies. They correspond to the version 2.2. Many fields are taken directly from the IRAS Point Source Catalogue (CDS Cat. II/125). See the IRAS Explanatory Supplement (Beichman et al., 1988, NASAR, 1190, 1) for more information. If there are problems that cannot be resolved by careful reading of these notes or the accompanying paper, please contact Will Saunders <will@roe.ac.uk> or Will Sutherland <W.Sutherland1@physics.ox.ac.uk>. This table was created by the HEASARC in February 2014 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/VII/221">CDS Catalog VII/221</a> files psczvs.dat (the 'Main' sample) and psczcgvs.dat (the 'Near-gap' sample), comprising the 'Short' version of the PSCz Catalog. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/lbqs
- Title:
- Large Bright Quasar Survey
- Short Name:
- LBQS
- Date:
- 10 May 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/lqac
- Title:
- Large Quasar Astrometric Catalog, 3rd Release
- Short Name:
- LQAC
- Date:
- 10 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- Since the release of the original Large Quasar Astrometric Catalog (LQAC: Souchay et al. 2009, A&A, 494, 815), a large number of quasars have been discovered through very dense observational surveys. Following the same procedure as in the first release of the LQAC, the authors aim is to compile all the quasars recorded up until the present date, with the best determination of their ICRS equatorial coordinates, i.e., with respect to the newly established ICRF2 (the second realization of the International Celestial Reference Frame) and with the maximum of information concerning their physical properties, e.g., redshifts, photometry, absolute magnitudes. In the second paper, the authors first of all made a substantial review of the definitions and properties of quasars and AGN (Active Galactic Nuclei), the differentiation of these objects being unclear in the literature and even for specialists. This served their purpose when deciding which kinds of objects would be taken into account in this compilation. Then, they carried out the cross-identification between the 9 catalogs of quasars chosen for their accuracy and their huge number of objects, using a flag for each of them, and including all the available data related to magnitudes (infrared and optical), radio fluxes and redshifts. They also performed cross identification with external catalogs 2MASS, B1.0 and GSC2.3 in order to complete photometric data for the objects. Moreover, they computed the absolute magnitude of their extragalactic objects by taking into account recent studies concerning Galactic absorption. In addition, substantial improvements were brought with respect to the first release of the LQAC. First, an LQAC name was given for each object based on its equatorial coordinates with respect to the ICRS, following a procedure which creates no ambiguity for identification. Secondly, the equatorial coordinates of the objects were recomputed more accurately according to the algorithms used for the elaboration of the Large Quasar Reference Frame (LQRF) (Andrei et al., 2009, <a href="https://cdsarc.cds.unistra.fr/ftp/cats/I/313">CDS Cat. I/313</a>). Thirdly, the authors introduced a morphological classification for the objects which enabled them in particular to define clearly if the object is point-like or extended. The authors adopted a cosmology with H<sub>0</sub> = 70 km s<sup>-1</sup> Mpc<sup>-1</sup>, Omega<sub>M</sub> = 0.3, Omega<sub>Lambda</sub> = 0.7, and q<sub>0</sub> = -0.65 in LQAC-3 (which is slightly different from that adopted for LQAC-2, notice). The final catalog, called LQAC-2, contained 187,504 quasars. This was roughly 65% larger than the 113,666 quasars recorded in the first version of the LQAC (Souchay et al. 2009, <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/494/799">CDS Cat. J/A+A/494/799</a>) and a little more than the number of quasars recorded in the up-dated version of the Veron-Cetty and Veron (2010, <a href="https://cdsarc.cds.unistra.fr/ftp/cats/VII/258">CDS Cat. VII/258</a>, HEASARC VERONCAT table) catalog, which was the densest compilation of quasars up to the present one. In addition to the quantitative and qualitative improvements implemented in this compilation, the authors discussed the homogeneity of the data and carried out a statistical analysis concerning the spatial density and the distance to the nearest neighbor in their published paper. The authors adopted a cosmology with H<sub>0</sub> = 72 km s<sup>-1</sup> Mpc<sup>-1</sup> and q<sub>0</sub> = -0.58 in this study. From an astrometric point of view, quasars constitute quasi-ideal reference objects in the celestial sphere, with an a priori absence of proper motion. Since the second release of the LQAC, a large number of quasars have been discovered, in particular with the upcoming new release of the SDSS quasars catalog. Following the same procedure as in the two previous releases of the LQAC, The authors' aim for LQAC-3 was to compile all the quasars recorded until the present date, with accurate recomputation of their equatorial coordinates in the ICRS and with the maximum of information concerning their physical properties, such as the redshift, the photometry, and the absolute magnitudes. The authors carried out the cross-identification between the 9 catalogs of quasars chosen for their huge number of objects, including all the available data related to magnitudes, radio fluxes, and redshifts. This cross identification was particularly delicate because of a slight change in coordinates between the objects common to two successive releases of the SDSS and the elimination of some of them. Equatorial coordinates were recomputed more accurately according to the algorithms used for the elaboration of the Large Quasar Reference Frame (LQRF). Moreover, absolute magnitudes and morphological indexes of the new objects were given, following the same method as in the LQAC-2. The final catalog, called LQAC-3, contains 321,957 objects including a small proportion of AGNs (14,128) and BL Lac objects (1,183). This is roughly 70% more than the number of objects recorded in the LQAC-2. The LQAC-3 will be useful for the astronomical community since it gives the most complete information available about the whole set of already recorded quasars, with emphasis on the precision and accuracy of their coordinates with respect to the ICRF2. This table was created by the HEASARC in June 2016 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/583/A75">CDS Catalog J/A+A/583/A75</a>, file lqac3.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/lcrscat
- Title:
- Las Campanas Redshift Survey Catalog
- Short Name:
- LCRSCAT
- Date:
- 10 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The Las Campanas Redshift Survey (LCRS) consists of 26,418 redshifts of galaxies selected from a CCD-based catalog obtained in the R band. The survey covers over 700 deg<sup>2</sup> in six strips, each 1.5 x 80 degrees, three each in the north and south Galactic caps. The median redshift in the survey is about 30,000 km s<sup>-1</sup>. Essential features of the galaxy selection and redshift measurement methods are described and tabulated in the reference paper. These details are important for subsequent analysis of the LCRS data. Two-dimensional representations of the redshift distributions reveal many repetitions of voids, on the scale of about 5000 km s<sup>-1</sup>, sharply bounded by large walls of galaxies as seen in nearby surveys. Statistical investigations of the mean galaxy properties and of clustering on the large scale are reported elsewhere. These include studies of the luminosity function, power spectrum in two and three dimensions, correlation function, pairwise velocity distribution, identification of large-scale structures, and a group catalog. This table contains entries for 94959 objects from the LCRS for which photometric data were obtained and which were initially classified as galaxies on the basis of this photometric information, although subsequent spectroscopy indicated that a small fracton of them are actually stars. There are 27021 objects out of this total which have spectroscopic redshift information (either of themselves or of a nearby object). See also the LCRS home pages at: <a href="http://qold.astro.utoronto.ca/~lin/lcrs.html">http://qold.astro.utoronto.ca/~lin/lcrs.html</a>. This table was created by the HEASARC in May 2010 based on the electronic version of Table 3 from the above reference which was obtained from the <a href="https://cdsarc.cds.unistra.fr/ftp/cats/VII/203">CDS Catalog VII/203</a> file catalog.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/markarian2
- Title:
- Markarian Galaxies Optical Database
- Short Name:
- MARKARIAN2
- Date:
- 10 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- A database for the entire Markarian (First Byurakan Spectral Sky Survey or FBS) Catalog is presented that combines extensive new measurements of their optical parameters with a literature and database search. The measurements were made using images extracted from the STScI Digitized Sky Survey (DSS) of F_pg (red) and J_pg (blue) band photographic sky survey plates obtained by the Palomar and UK Schmidt telescopes. The authors provide accurate coordinates, morphological type, spectral and activity classes, red and blue apparent magnitudes, apparent diameters, axial ratios, and position angles, as well as number counts of neighboring objects in a circle of radius 50 kpc. Special attention was paid to the individual descriptions of the galaxies in the original Markarian lists, which clarified many cases of misidentifications of the objects, particularly among interacting systems, larger galaxies with knots of star formation, possible stars, and cases of stars projected on galaxies. The total number of individual Markarian objects in the database is now 1544. The authors also have included redshifts which are now available for 1524 of the objectswith UV-excess radiation, as well as Galactic color excess E(B-V) values and their 2MASS or DENIS infrared magnitudes. The table also includes extensive notes that summarize information about the membership of Markarian galaxies in different systems of galaxies and about new and revised activity classes and redshifts. The new optical information on Markarian galaxies was obtained from images extracted from the STScI Digitized Sky Survey (DSS) of F_pg (red) and J_pg (blue) band photographic sky survey plates obtained by the Palomar and UK Schmidt telescopes. This table was created by the HEASARC in November 2009 based on the electronic version of the optical database of Markarian galaxies which was obtained from the CDS (their catalog J/ApJS/170/33 file table1.dat). This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/twomassrsc
- Title:
- 2MASS Redshift Survey (2MRS) Catalog
- Short Name:
- TWOMASSRSC
- Date:
- 10 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table is based on the results of the 2MASS Redshift Survey (2MRS), a ten-year project to map the full three-dimensional distribution of galaxies in the nearby universe. The Two Micron All Sky Survey (2MASS) was completed in 2003 and its final data products, including an extended source catalog (XSC), are available online. The 2MASS XSC contains nearly a million galaxies with K<sub>s</sub> <= 13.5 mag and is essentially complete and mostly unaffected by interstellar extinction and stellar confusion down to a galactic latitude of |b| = 5 degrees for bright galaxies. Near-infrared wavelengths are sensitive to the old stellar populations that dominate galaxy masses, making 2MASS an excellent starting point to study the distribution of matter in the nearby universe. The authors selected a sample of 44,599 2MASS galaxies with K<sub>s</sub> <= 11.75 mag and |b| >= 5 degrees (>= 8 degrees toward the Galactic bulge) as the input catalog for their survey. They obtained spectroscopic observations for 11,000 galaxies and used previously obtained velocities for the remainder of the sample to generate a redshift catalog that is 97.6% complete to well-defined limits and covers 91% of the sky. This provides an unprecedented census of galaxy (baryonic mass) concentrations within 300 Mpc. Earlier versions of their survey have been used in a number of publications that have studied the bulk motion of the Local Group, mapped the density and peculiar velocity fields out to 50 h<sup>-1</sup> Mpc, detected galaxy groups, and estimated the values of several cosmological parameters. Additionally, the authors present morphological types for a nearly complete sub-sample of 20,860 galaxies with K<sub>s</sub> <= 11.25 mag and |b| >= 10 degrees. The authors initially selected 45,086 sources which met the following criteria: <pre> K<sub>s</sub> <= 11.75 mag and detected at H, E(B - V) <= 1 mag, |b| >= 5 degrees for 30 degrees < l < 330 degrees, |b| >= 8 degrees otherwise. </pre> They rejected 324 sources of galactic origin (multiple stars, planetary nebulae, and H II regions) or pieces of galaxies detected as separate sources by the 2MASS pipeline. Additionally, they flagged 314 bona fide galaxies with compromised photometry for reprocessing at a future date. Some of these galaxies have bright stars very close to their nuclei which were not detected by the pipeline. Others are in regions of high stellar density and their center positions and/or isophotal radii have been incorrectly measured by the pipeline. Lastly, some are close pairs or multiples but the pipeline only identified a single object. A detailed explanation of the steps taken to reject and reprocess the flagged galaxies is given in the Appendix of the reference paper. In summary, the final input catalog contained here has 44,599 entries (plotted using black symbols in Figure 1 of the reference paper). In this table, redshifts for 43,533 of the selected galaxies, or 97.6% of the sample, are presented. This table was created by the HEASARC in April 2012 based on an electronic version of Table 3 of the reference paper which was obtained from the ApJS website. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/mcxc
- Title:
- MCXC Meta-Catalog of X-Ray Detected Clusters of Galaxies
- Short Name:
- MCXC
- Date:
- 10 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The MCXC is the Meta-Catalog of the compiled properties of X-ray detected Clusters of galaxies. This very large catalog is based on publicly available ROSAT All Sky Survey (RASS)-based (NORAS, REFLEX, BCS, SGP, NEP, MACS, and CIZA) and ROSAT serendipitous (160SD, 400SD, SHARC, WARPS, and EMSS) cluster catalogs. Data have been systematically homogenised to an overdensity of 500, and duplicate entries from overlaps between the survey areas of the individual input catalogs have been carefully handled. The MCXC comprises 1743 clusters with virtually no duplicate entries. For each cluster, the MCXC provides three identifiers, a redshift, coordinates, membership in the original catalog, and standardised 0.1 - 2.4 keV band luminosity Lx<sub>500</sub>, total mass M<sub>500</sub>, and radius R<sub>500</sub>, where the 500 suffix means that the quantity has been calculated up to a standard characteristic radius R<sub>500</sub>, the radius within which the mean overdensity of the cluster is 500 times the critical density at the cluster redshift . The meta-catalog additionally furnishes information on overlaps between the input catalogs and the luminosity ratios when measurements from different surveys are available, and gives notes on individual objects. The MCXC is made available so as to provide maximum usefulness for X-ray, Sunyaev-Zel'dovich (SZ) and other multiwavelength studies. The catalogs and sub-catalogs included in this meta-catalog are listed in Table 1 of the reference paper, and come from the following references: <pre> Catalog Sub- Reference Title Catalog or CDS Cat. (Author) RASS IX/10 ROSAT All-Sky Bright Source Catalog (1RXS) (Voges+, 1999) BCS BCS J/MNRAS/301/881 ROSAT brightest cluster sample - I. (Ebeling+, 1998) eBCS J/MNRAS/318/333 Extended ROSAT Bright Cluster Sample (Ebeling+ 2000) CIZA X-ray clusters behind the Milky Way CIZAI ApJ, 580, 774 (Ebeling+, 2002) CIZAII J/APJ/662/224 (Kocevski+, 2007) EMSS ApJS, 72, 567 Einstein Extended Medium Sensitivity Survey (Gioia+, 1990) EMSS_1994 ApJS, 94, 583 (Gioia & Luppino, 1994) EMSS_2004 ApJ, 608, 603 (Henry 2004) MACS ApJ, 553, 668 Massive Cluster Survey (Ebeling+, 2001) MACS_MJFV ApJS, 174, 117 (Maughan+, 2008) MACS_BRIGHT MNRAS, 407, 83 (Ebeling+, 2010) MACS_DIST ApJ, 661, L33 (Ebeling+, 2007) NEP NEP J/ApJS/162/304 ROSAT NEP X-ray source catalog (Henry+, 2006) NORAS/ REFLEX NORAS J/ApJS/129/435 NORAS galaxy cluster survey. I. (Boehringer+, 2000) REFLEX J/A+A/425/367 REFLEX Galaxy Cluster Survey Cat (Boehringer+, 2004) SGP SGP J/ApJS/140/239 Clusters of galaxies around SGP (Cruddace+, 2002) SHARC SHARC_BRIGHT J/ApJS/126/209 Bright SHARC survey cluster catalog (Romer+, 2000) SHARC_SOUTH J/MNRAS/341/1093 The Southern SHARC catalog (Burke+, 2003) WARPS WARPSI J/ApJS/140/265 WARPS survey. VI. (Perlman+, 2002) WARPSII J/ApJS/176/374 WARPS-II Cluster catalog. VII. (Horner+, 2008) 160SD 160SD J/ApJ/594/154 160 square degree ROSAT Survey (Mullis+, 2003) 400SD J/ApJS/172/561 400 square degree ROSAT Cluster Survey (Burenin+, 2007) 400SD_SER Serendipitous clusters 400SD_NONSER Not entirely serendipitous clusters </pre> This table was originally ingested by the HEASARC in October 2011 based on the <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/534/A109">CDS catalog J/A+A/534/A109</a> file mcxc.dat. It was last updated in September 2023 to match the 12-Nov-2011 CDS version of the catalog. This update corrected the missing minus signs in the declinations of 6 clusters and homogenized the Abell object names. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/milliquas
- Title:
- Million Quasars Catalog (MILLIQUAS), Version 8 (2 August 2023)
- Short Name:
- MILLIQUAS
- Date:
- 10 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains the Million Quasars (MILLIQUAS) Catalog, Version 8 (2 August 2023). It is a compendium of 907,144 type-I QSOs and AGN, largely complete from the literature to 30 June 2023. 66,026 QSO candidates are also included, calculated via radio/X-ray association (including double radio lobes) as being 99% likely to be quasars. Blazars and type-II objects are also included, bringing the total count to 1,021,800. 60.7% of all objects show Gaia-EDR3 astrometry. Low-confidence/quality or questionable objects (so deemed by their researchers) are not included in Milliquas. Additional quality cuts can be applied as detailed in the HMQ paper (Flesch 2015,PASA,32,10). Full QSO/AGN classification is accomplished via spectral lines, yielding a reliable spectroscopic redshift. Two spectral lines are required, or one spectral line refining a compatible photometric redshift. Obscured AGN with redshifts from the hosts only are taken to be type-II objects. Some legacy quasars with neither good spectra nor radio/X-ray association were flagged by Gaia-EDR3 as 5-sigma moving (i.e., stars), and so were removed from Milliquas. All objects are de-duplicated across source catalogs. The author's aim here is to present one unique reliable object per each data row. Two NIQs offset < 2 arcsec can be reported as a single object if within the same host. Lenses are reported as single objects onto the brightest quasar imaged. (Milliquas is not a catalog of lenses.) The contents are relatively simple; each object is shown as one entry with the sky coordinates (of whatever epoch), its original name, object class, red and blue optical magnitudes, PSF class, redshift, the citations for the name and redshift, and up to four radio/X-ray identifiers where applicable. Questions/comments/praise/complaints may be directed to Eric Flesch at eric@flesch.org. If you use this catalog in published research, the author requests that you please cite it. The confirmed quasars of this catalog (to Jan 2015) were published as the Half Million Quasars (HMQ) catalog: Flesch E., 2015,PASA,32,10. Note however that Milliquas uses optical sky data from ASP (2017,PASA,34,25) whereas the HMQ used optical sky data from QORG (2004,A&A,427,387) Appendix A. This table was updated by the HEASARC in July 2023 based on a machine-readable catalog obtained from the author's MILLIQUAS website at <a href="https://quasars.org/milliquas.htm">https://quasars.org/milliquas.htm</a>. <p> This research has made use of the NASA/IPAC Extragalactic Database (NED) which is operated by the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration. <p> This research has made use of the SIMBAD database and CDS cross-match service (to obtain Gaia-EDR3 and Pan-STARRS photometry) provided by CDS, Strasbourg, France. <a href="https://simbad.cds.unistra.fr/simbad">https://simbad.cds.unistra.fr/simbad</a> This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/mcg
- Title:
- Morphological Galaxy Catalog
- Short Name:
- MCG
- Date:
- 10 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The MCG database contains the "Morphological Catalogue of Galaxies," a compilation of information for approximately 34,000 galaxies found and examined on the Palomar Observatory Sky Survey (POSS). Individual identifiers are assigned for about 29,000 galaxies and information on the remaining 5,000 is present in the extensive notes of the published catalogs (Vorontsov-Velyaminov et al. 1962-1968). The catalog is structured according to the POSS zones and is numbered from +15 (corresponding to +90 deg) to +01 (+06 deg zone) and +00 (equatorial zone) to -05 (-30 deg zone); the fields are numbered with increasing right ascension. The original goal of the compilation was to be complete for galaxies brighter than magnitude 15.1, but the final catalog lists many objects considerably fainter. Information given in the original printed volumes includes: cross- identifications to the NGC (Dreyer 1888) and IC (Dreyer 1895, 1908) catalogs, equatorial coordinates for 1950.0, magnitude, estimated sizes and intensities of the bright inner region and the entire object, estimated inclination, and coded description (by symbols) of the appearance of the galaxy. Each field is then followed by notes on individual objects. All of the above data except the coded description are included in the machine version, except that special coding (e.g. for uncertainty or source designation) is not present (other than for the NGC/IC cross identifications [added at the Astronomical Data Center for this machine version]). Although the notes are not computerized, the presence of a note in the original is flagged in the machine version Detailed descriptions of modifications, corrections and the record format are provided for the machine-readable version of the "Morphological Catalogue of Galaxies" (Vorontsov-Velyaminov et al. 1962-68); see the Additional Information section below. In addition to hundreds of individual corrections, a detailed comparison of the machine-readable with the published catalog resulted in the addition of 116 missing objects, the deletion of 10 duplicate records, and a format modification to increase storage efficiency. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/noras
- Title:
- Northern ROSAT All-Sky (NORAS) Galaxy Cluster Survey Catalog
- Short Name:
- NORASGalClus
- Date:
- 10 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- In the construction of an X-ray-selected sample of galaxy clusters for cosmological studies, the authors have assembled a sample of 495 X-ray sources which were found to show extended X-ray emission in the first processing of the ROSAT All-Sky Survey (RASS I), the Northern ROSAT All-Sky (NORAS) Galaxy Cluster Survey Catalog. The sample covers the celestial region with declination >=0 degrees and Galactic latitude |b| >= 20 degrees, and comprises sources with a Position Sensitive Proportional Counter (PSPC) count rate >= 0.06 counts/s and a source extent likelihood of L >= 7. In an optical follow-up identification program, the authors found 378 (76%) of these sources to be clusters of galaxies. It was necessary to reanalyze the sources in this sample with a new X-ray source characterization technique to provide more precise values for the X-ray flux and source extent than obtained from the standard processing. This new method, termed growth curve analysis (GCA), has the advantage over previous methods in its ability to be robust, to be easy to model and to integrate into simulations, to provide diagnostic plots for visual inspection, and to make extensive use of the X-ray data. The source parameters obtained assist the source identification and provide more precise X-ray fluxes. This reanalysis is based on data from the more recent second processing of the ROSAT Survey, RASS II. The authors present a catalog of the cluster sources with the X-ray properties obtained as well as a list of the previously flagged extended sources that are found to have a non-cluster counterpart. In their paper, they discuss the process of source identification from the combination of optical and X-ray data. To investigate the overall completeness of the cluster sample as a function of the X-ray flux limit, they extended the search for X-ray cluster sources to the RASS II data for the northern sky region between 9 and 14 hours in right ascension. They included the search for X-ray emission from known galaxy clusters as well as a new investigation of extended X-ray sources. In the course of this search, they found X-ray emission from 85 additional Abell clusters and 56 very probable cluster candidates among the newly found extended sources. A comparison of the X-ray cluster number counts of the NORAS sample with the ROSAT-ESO Flux-limited X-ray (REFLEX) Cluster Survey results leads to an estimate of the completeness of the NORAS sample of ROSAT All-Sky Survey (RASS) I extended clusters of about 50% at an X-ray flux of FX(0.1-2.4 keV) = 3 x 10-12 ergs s<sup>-1</sup> cm<sup>-2</sup>. The estimated completeness achieved by adding the supplementary sample in the study area amounts to about 82% in comparison to REFLEX. The low completeness introduces an uncertainty in the use of the sample for cosmological statistical studies that will be cured with the completion of the continuing Northern ROSAT All-Sky (NORAS) Cluster Survey project. This table was created by the HEASARC in June 2005 based on CDS table J/ApJS/129/435, table1.dat through table9.dat inclusive. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/osrilqxray
- Title:
- Optically Selected Radio-Intermediate and Loud Quasars X-ray Emission Catalog
- Short Name:
- OSRILQXRAY
- Date:
- 10 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This catalog contains some of the results of an investigation into the X-ray properties of radio-intermediate and radio-loud quasars (RIQs and RLQs, respectively). The authors have combined large, modern optical (e.g., SDSS) and radio (e.g., FIRST) surveys with archival X-ray data from Chandra, XMM-Newton, and ROSAT to generate an optically selected sample that includes 188 RIQs and 603 RLQs. This sample is constructed independently of X-ray properties but has a high X-ray detection rate (85%); it provides broad and dense coverage of the luminosity-redshift (l-z) plane, including at high redshifts (22% of the objects have z = 2-5), and it extends to high radio-loudness R<sub>L</sub> values (33% of objects have R<sub>L</sub> = log(L<sub>r</sub>/L<sub>o</sub>) = 3 - 5), where L<sub>r</sub> and L<sub>o</sub> are the rest-frame monochromatic luminosities at 5 GHz and 2500 Angstroms, respectively). The authors measure the "excess" X-ray luminosity of RIQs and RLQs relative to radio-quiet quasars (RQQs) as a function of radio loudness and luminosity, and parametrize the X-ray luminosity of RIQs and RLQs both as a function of optical/UV luminosity and also as a joint function of optical/UV and radio luminosity. RIQs are only modestly X-ray bright relative to RQQs; it is only at high values of radio loudness (R<sub>L</sub> >~ 3.5) and radio luminosity that RLQs become strongly X-ray bright. This HEASARC table contains the primary sample from the reference paper. The authors consider three categories of quasars in this work: RQQs, RIQs, and RLQs (rather than just RQQs and RLQs), where the define RIQs to consist of objects with 1 <= R<sub>L</sub> < 2; consequently, the objects they classify as RLQs satisfy R<sub>L</sub> >= 2. The primary sample contained herein consists of 654 optically selected RIQs and RLQs with SDSS/FIRST observations and high-quality X-ray coverage from Chandra (171), XMM-Newton (202), or ROSAT (281). The primary sample is split nearly evenly between spectroscopic (312) and high-confidence photometric (342) quasars. Most (562) of the primary sample objects possess serendipitous off-axis X-ray coverage, while the remainder (92) were targeted in the observations used in this sample. The X-ray detection fraction for the primary sample is 84%; the detection fraction for those objects with Chandra/XMM-Newton/ROSAT coverage is 95%/92%/70% (typical ROSAT observations are comparatively less sensitive and have higher background). The authors adopt a standard cosmology with H<sub>0</sub> = 70 km s<sup>-1</sup> Mpc<sup>-1</sup>, Omega<sub>M</sub> = 0.3, and Omega<sub>Lambda</sub> = 0.7 throughout their study. This table was created by the HEASARC in October 2012 based on CDS Catalog J/ApJ/726/20 file table1.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/pgc2003
- Title:
- Principal Galaxy Catalog (PGC) 2003
- Short Name:
- PGC
- Date:
- 10 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The Principal Galaxy Catalog, 2003 Version (PGC2003) is a new catalog of principal galaxies. It constitutes the framework of the HYPERLEDA database that supersedes the LEDA one, with more data and more capabilities. The catalog is still restricted to confirmed galaxies, i.e. about one million galaxies, brighter than a B-magnitude of ~18. In order to provide the best possible identification for each galaxy, the authors give accurate coordinates (typical accuracy of better than 2 arcseconds), diameters, axis ratios and position angles. Diameters and axis ratios have been homogenized to the RC2 system at the limiting surface brightness of 25 B-mag/arcsec<sup>2</sup>, using a new method (EPIDEMIC). In order to provide the best designation for each galaxy, the authors have collected names from 50 catalogs. The compatibility of the spelling has been tested against NED and SIMBAD, and, as far as possible a spelling is used that is compatible with both. For some cases, where no consensus exists between NED, SIMBAD and LEDA, the authors have proposed some changes that could make the spelling of names fully compatible. The full catalog is distributed through the CDS and can be extracted from HYPERLEDA, <a href="http://leda.univ-lyon1.fr/">http://leda.univ-lyon1.fr/</a>. This table was created by the HEASARC in July 2004 based on the <a href="https://cdsarc.cds.unistra.fr/ftp/cats/VII/237">CDS catalog VII/237</a> file pgc.dat.gz. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/romabzcat
- Title:
- Roma-BZCAT Multi-Frequency Catalog of Blazars
- Short Name:
- ROMABZCAT
- Date:
- 10 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains the 5th edition of the Roma-BZCAT catalog of blazars which contains coordinates and multi-frequency data of 3561 sources. It presents several relevant changes with respect to the past editions which are briefly described in the reference paper. The Roma-BZCAT catalog contains data on 3561 sources, about 30% more than in the 1st edition, which either confirmed blazars or exhibiting characteristics close to this type of sources. With respect to the previous editions, this new edition has relevant changes in the sources' classification. The authors emphasize that all the sources in the Roma-BZCAT have a detection in the radio band. Moreover, complete spectroscopic information is published and could be accessed by the authors for all of them, with the exception of BL Lac candidates. Consequently, peculiar sources such as the so called "radio quiet BL Lacs", which are reported in some other catalogs, are not included here because of possible contamination by hot stars and other extragalactic objects. In the 5th edition, the authors use a similar denomination for the blazars to that adopted in the previous editions. Each blazar is identified by a code, with 5BZ for all blazars, a fourth letter that specifies the type (B, G, Q or U), followed by the truncated equatorial coordinates (J2000). The authors introduced the edition number before the letters BZ to avoid possible confusion due to the fact that several sources changed their old names because of a newly adopted classification. The 5th edition contains 1151 BZB sources (92 of which are reported as candidates because their optical spectra could not be found in the literature), 1909 BZQ sources, 274 BZG sources, and 227 BZU objects. This database table was originally ingested by the HEASARC in September 2013, based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/495/691">CDS Catalog J/A+A/495/691</a> file bzcat4.dat. It was updated in March 2016, and it is now based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/VII/274">CDS Catalog VII/274</a> file bzcat5.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/rassdssagn
- Title:
- ROSAT All-Sky Survey and SDSS DR5 Sample of X-Ray Emitting AGN
- Short Name:
- RASS/SDSSAGN
- Date:
- 10 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains further results of a program aimed at yielding ~ 10<sup>4</sup> fully characterized optical identifications of ROSAT X-ray sources. The program employs X-ray data from the ROSAT All Sky Survey (RASS) and both optical imaging and spectroscopic data from the Sloan Digital Sky Survey (SDSS). RASS/SDSS data from 5740 deg<sup>2</sup> of sky spectroscopically covered in SDSS Data Release 5 (DR5) provide an expanded catalog of 7000 confirmed quasars and other active galactic nuclei (AGN) that are probable RASS identifications. Again, in this expanded catalog the identifications as X-ray sources are statistically secure, with only a few percent of the SDSS AGNs likely to be randomly superposed on unrelated RASS X-ray sources. Most identifications continue to be quasars and Seyfert 1 galaxies with 15 < m < 21 and 0.01 < z < 4, but the total sample size has grown to include very substantial numbers of even quite rare AGN, e.g., it now includes several hundreds of candidate X-ray-emitting BL Lac objects and narrow-line Seyfert 1 galaxies. In addition to exploring rare subpopulations, such a large total sample may be useful when considering correlations between the X-ray and the optical and may also serve as a resource list from which to select the ``best'' object (e.g., the X-ray-brightest AGN of a certain subclass at a preferred redshift or luminosity) for follow-up X-ray spectral or alternate detailed studies. 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 combination of the electronic versions of tables 1 through 6 from the above reference which were obtained from the electronic AJ website. It replaces a previous version containing the results presented by Anderson et al. (2003, AJ, 126, 2209) which were based on a cross-correlation of the RASS with optical data from very early on in the SDSS program, e.g., extending back to the 'Early Data Release' before SDSS photometric calibrations were complete. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/rasssdssgc
- Title:
- ROSAT All-Sky Survey and Sloan Digital Sky Survey DR7 Galaxy Clusters
- Short Name:
- RASSSDSSGC
- Date:
- 10 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The authors use ROSAT All-Sky Survey (RASS) broad-band X-ray images and the optical clusters identified from the Sloan Digital Sky Survey Data Release 7 (SDSS DR7) to estimate the X-ray luminosities around ~65,000 candidate galaxy clusters with masses >~10<sup>13</sup> h<sup>-1</sup> M<sub>sun</sub> based on an optical to X-ray (OTX) code that they developed. They obtain a catalog with X-ray luminosities for all 64,646 clusters. A total of 34,522 (~53%) of these clusters have a signal-to-noise ratio S/N > 0 after subtracting the background signal. According to the reference paper (but see HEASARC Caveats section below), this catalog contains 817 clusters (473 at redshift z <= 0.12) with S/N > 3 for their X-ray detections (an additional 12,629 clusters have 3 >= S/N > 1 and 21,076 clusters have 1 >= S/N > 0). The authors find about 65% of these X-ray clusters have their most massive member located near the X-ray flux peak; for the remaining 35%, the most massive galaxy is separated from the X-ray peak, with the separation following a distribution expected from a Navarro-Frenk-White profile. In the reference paper, the authors investigate a number of correlations between the optical and X-ray properties of these X-ray clusters, and find that the cluster X-ray luminosity is correlated with the stellar mass (luminosity) of the clusters, as well as with the stellar mass (luminosity) of the central galaxy and the mass of the halo, although the scatter in these correlations is large. Comparing the properties of X-ray clusters of similar halo masses but having different X-ray luminosities, they find that massive haloes with masses >~10<sup>14</sup> h<sup>-1</sup> M<sub>sun</sub> contain a larger fraction of red satellite galaxies when they are brighter in X-ray. An opposite trend is found in central galaxies in relative low-mass haloes with masses <~10<sup>14</sup> h<sup>-1</sup> M<sub>sun</sub> where X-ray brighter clusters have smaller fraction of red central galaxies. Clusters with masses >~10<sup>14</sup> h<sup>-1</sup> M<sub>sun</sub> that are strong X-ray emitters contain many more low-mass satellite galaxies than weak X-ray emitters. These results are also confirmed by checking X-ray clusters of similar X-ray luminosities but having different characteristic stellar masses. The cluster catalog containing the optical properties of member galaxies and the X-ray luminosity is also available at <a href="http://gax.shao.ac.cn/data/Group.html">http://gax.shao.ac.cn/data/Group.html</a>. The optical data used in this analysis are taken from the SDSS galaxy group catalogs of Yang et al. (2007, ApJ, 671, 153), constructed using the adaptive halo-based group finder of Yang et al. (2005, MNRAS, 356, 1293), here updated to DR7. The parent galaxy catalog is the New York University Value-Added Galaxy Catalog (NYU-VAGC; Blanton et al. 2005, AJ, 129, 2562) based on the SDSS DR7 (Abazajian et al. 2009, ApJS, 182, 543), which contains an independent set of significantly improved reductions. In this study, the authors adopt a Lambda cold dark matter cosmology whose parameters are consistent with the 7-year data release of the WMAP mission: Omega<sub>m</sub> = 0.275, Omega<sub>Lambda</sub> = 0.725, h = H<sub>0</sub>/(100 km s<sup>-1</sup> Mpc<sup>-1</sup>) = 0.702, and sigma<sub>8</sub> = 0.816. This table was created by the HEASARC in June 2017 based upon the <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/MNRAS/439/611">CDS Catalog J/MNRAS/439/611</a> file catalog.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/rassbscpgc
- Title:
- ROSAT All-Sky Survey Bright Source Catalog/Catalog of Principal Galaxies Matches
- Short Name:
- RASSBSCPGC
- Date:
- 10 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- In a correlation study of the ROSAT All-Sky Survey Bright Source Catalog (RASS-BSC, <a href="https://cdsarc.cds.unistra.fr/ftp/cats/XI/10">CDS Cat. <XI/10></a>, the HEASARC table RASSBSC) with the Catalogue of Principal Galaxies (PGC, <a href="https://cdsarc.cds.unistra.fr/ftp/cats/VII/119">CDS Cat. <VII/119></a>, the HEASARC table PGC2003), 904 X-ray sources were found that possess possible extragalactic counterparts within a search radius of 100 arcseconds. A visual screening process was applied to classify the reliability of the correlations. 547 correlations have been quoted as reliable identifications. From these, 349 sources are known to be active galaxies. Although for the other sources no hints for activity were found in the literature, 69% of those for which we have distances show X-ray luminosities exceeding those of normal galaxies, a clear sign that these galaxies also own hitherto unreported X-ray active components. Some objects are located inside or in the direction of a known group or cluster of galaxies. Their X-ray flux may therefore be in part affected by hot gas emission. In the paper, luminosity and log N-log S distributions are used to characterize different subsamples. Nuclei that are both optically and X-ray active are found predominantly in spirals. Two special source samples are defined, one with candidates for X-ray emission from hitherto unknown groups or clusters of galaxies, and one with high X-ray luminosity sources, that are likely candidates to possess hitherto unreported active galactic nuclei. Besides a compilation of X-ray and optical parameters, X-ray overlays on optical images for all the objects are also supplied as part of this work. This table contains 1124 optical galaxy entries for the 904 relevant X-ray candidates/counterparts from the RASS. Besides a compilation of X-ray and optical parameters for each source, the results of an identification screening are also given. The 904 optical images with X-ray overlay contours (xID_nnn.ps.gz) used in the screening process are added for each user's own judgement of the reliability of the associations. This table was created by the HEASARC in March 2012 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/378/30">CDS catalog J/A+A/378/30</a> file table1.dat, the list of PGC galaxies identified as possible counterparts to RASS Bright Source Catalog X-ray sources. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/rasscals
- Title:
- ROSAT All-Sky Survey CALS Galaxy Groups Catalog
- Short Name:
- RASS-CALS
- Date:
- 10 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains the catalog from the ROSAT All-Sky Survey (RASS) Center for Astrophysics (CfA) Loose Systems, or RASSCALS, the largest X-ray and optical survey of low-mass galaxy groups as of its publication date in 2000. The authors drew 260 groups from the combined Center for Astrophysics and Southern Sky Redshift Surveys, covering one-quarter of the sky to a limiting Zwicky magnitude of m<sub>z</sub> = 15.5. They detected 61 groups (23%) as extended X-ray sources. The X-ray detections have a median membership of nine galaxies, a median recession velocity cz = 7250 km/s, a median projected velocity dispersion sigma(p) = 400 km/s, and a median X-ray luminosity L(x) = 3 x 10<sup>42</sup> /h(100)<sup>2</sup> erg/s, where the Hubble constant is H(0) = 100 h(100) km/s/Mpc. The data in this table replace the preliminary analysis of the X-ray data which was presented in Mahdavi et al., 1999, ApJ, 518, 69 (CDS Cat. <J/ApJ/518/69>. This table was created by the HEASARC in September 2005 based on CDS tables J/ApJ/534/114/table2.dat & table3.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/rass6dfgs
- Title:
- ROSAT All-Sky Survey/6dF Galaxy Survey Catalog of X-Ray Selected AGN
- Short Name:
- RASS6DFGS
- Date:
- 10 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains a catalog of 3405 X-ray sources from the ROSAT All Sky Survey (RASS) Bright Source Catalog which fall within the area covered by the 6dF Galaxy Survey (6dFGS). The catalog is count-rate limited at 0.05 ct s<sup>-1</sup> in the X-ray and covers the area of sky with Declination < 0 degrees and |b| > 10 degrees. The RASS-6dFGS sample was one of the additional target catalogs of the 6dFGS and as a result the authors obtained optical spectra for 2224 (65 per cent) RASS sources. Of these, 1715 (77%) have reliable redshifts with a median redshift of z = 0.16 (excluding the Galactic sources). For the optically bright sources (b_J <= 17.5) in the observed sample, over 90% have reliable redshifts. The catalog mainly comprises quasi-stellar objects (QSOs) and active galaxies but also includes 238 Galactic sources. Of the sources with reliable redshifts, the majority are type 1 active galactic nuclei (AGN, 69%), while 12% are type 2 AGN, 6% absorption-line galaxies and 13% are stars. The authors also identify a small number of optically faint, very low redshift, compact objects which fall outside the general trend in the b_J - z plane. The RASS-6dFGS catalog complements a number of Northern hemisphere samples, particularly the ROSAT Bright Source Catalogue-NRAO VLA Sky Survey (RBSC-NVSS) sample (Bauer et al. 2000, ApJS, 129, 547), and furthermore, in the same region of sky (-40 degrees < Declination < 0 degrees) reveals an additional 561 sources that were not identified as part of that sample. The authors detect 918 sources (27%) of the RASS-6dFGS sample in the radio using either the 1.4 GHz NVSS or the 843 MHz Sydney University Molonglo Sky Survey (SUMSS) catalogues and find that the detection rate changes with redshift. At redshifts larger than 1 virtually all of these sources have radio counterparts and with a median flux density of 1.15 Jy, they are much stronger than the median flux density of 28.6 mJy for the full sample. The authors attribute this to the fact that the X-ray flux of these objects is being boosted by a jet component, possibly Doppler boosted, that is only present in radio-loud AGN. The RASS-6dFGS sample provides a large set of homogeneous optical spectra ideal for future studies of X-ray emitting AGN. This table was created by the HEASARC in April 2010 based on an electronic version of Table 3 from the reference paper obtained from the MNRAS web site. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/rassebcs
- Title:
- ROSAT All-Sky Survey Extended Brightest Cluster Sample
- Short Name:
- RASSBCS
- Date:
- 10 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains the ROSAT All-Sky Survey (RASS) Brightest Cluster Sample (BCS) and the Low-Flux Extension, which together form the Extended BCS (eBCS). The main BCS, which was presented in Ebeling et al. (1998, MNRAS, 301, 881; Paper I), is a 90% flux-complete sample of the 201 X-ray-brightest clusters of galaxies in the northern hemisphere (Dec >=0 degrees), at high Galactic latitudes (|b| >= 20 degrees), with measured redshifts z <= 0.3 and X-ray fluxes higher than 4.4 x 10<sup>-12</sup> erg/cm<sup>2</sup>/s in the 0.1 - 2.4 keV band. This sample, called the ROSAT Brightest Cluster Sample, is selected from RASS data and is the largest X-ray-selected cluster sample compiled to the publication date (1998). In addition to Abell clusters which form the bulk of the sample, the BCS also contains the X-ray-brightest Zwicky clusters and other clusters selected from their X-ray properties alone. Effort has been made to ensure the highest possible completeness of the sample and the smallest possible contamination by non-cluster X-ray sources. X-ray fluxes were computed using an algorithm tailored for the detection and characterization of X-ray emission from galaxy clusters. These fluxes are accurate to better than 15% (mean 1-sigma error). The low-flux extension of the X-ray-selected ROSAT Brightest Cluster Sample was published in Ebeling et al. (2000, MNRAS, 318, 333; Paper IV). Like the original BCS and employing an identical selection procedure, the BCS extension is compiled from ROSAT All-Sky Survey (RASS) data in the northern hemisphere (Dec >=0 degrees) and at high Galactic latitudes (|b| >= 20 degrees). It comprises 99 X-ray-selected clusters of galaxies with measured redshifts z <= 0.3 (as well as eight more at z > 0.3) and total fluxes between 2.8 x 10<sup>-12</sup> and 4.4 x 10<sup>-12</sup> erg/cm<sup>2</sup>/s in the 0.1 - 2.4keV band (the latter value being the flux limit of the original BCS). The extension can be combined (as it has been in this HEASARC table) with the main sample published in 1998 to form the homogeneously selected extended BCS (eBCS), the largest and statistically best understood cluster sample to emerge from the RASS to date. The nominal completeness of the combined sample (defined with respect to a power-law fit to the bright end of the BCS log N -log S distribution) is relatively low at 75% (compared with 90% for the high-flux sample of Paper I). However, just as for the original BCS, this incompleteness can be accurately quantified, and thus statistically corrected for, as a function of X-ray luminosity and redshift. In addition to its importance for improved statistical studies of the properties of clusters in the local Universe, the low-flux extension of the BCS is also intended to serve as a finding list for X-ray-bright clusters in the northern hemisphere which the authors hoped will prove useful in the preparation of cluster observations to be made with the next generation of X-ray telescopes such as Chandra and XMM-Newton. This table was created by the HEASARC in August 2005 based on the merger of 2 CDS tables, J/MNRAS/301/881/table3.dat.gz (the main sample) and J/MNRAS/318/333/table1.dat.gz (the low-flux extension). This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/reflex
- Title:
- ROSAT-ESO Flux-Limited X-Ray (REFLEX) Galaxy Cluster Survey
- Short Name:
- ROSAT/ESOClus.
- Date:
- 10 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table is the ROSAT-ESO Flux-Limited X-Ray (REFLEX) Galaxy Cluster Survey Catalog. The REFLEX Cluster Survey provides information on the X-ray properties, redshifts, and some identification details of clusters in the REFLEX sample. The catalog describes a statistically complete X-ray flux-limited sample of 447 galaxy clusters above an X-ray flux of 3 x 10<sup>-12</sup> erg/s/cm<sup>2</sup> (0.1 to 2.4 keV) in an area of 4.24 steradians in the southern sky. The cluster candidates were first selected by their X-ray emission in the ROSAT-All Sky Survey and subsequently spectroscopically identified in the frame of an ESO key program. Previously described tests have shown that the sample is more than 90% complete and there is a conservative upper limit of 9% on the fraction of clusters with a dominant X-ray contamination from AGN. This data set is at present the largest, statistically complete X-ray galaxy cluster sample. The sample forms the basis of several cosmological studies, one of the most important applications being the assessment of the statistics of the large-scale structure of the universe and the test of cosmological models. The X-ray luminosities and other distance-dependent cluster parameters are calculated for a Lambda cosmology with a Hubble Constant H<sub>0</sub> of 70 km/s/Mpc, Omega<sub>M</sub> of 0.3, and Omega<sub>Lambda</sub> of 0.7. The CDS version of this catalog contains an additional table (reflex50.dat) with these parameters calculated for an Einstein-de Sitter universe with H<sub>0</sub> = 50 km/s/Mpc, Omega<sub>M</sub> = 1.0, and Omega<sub>Lambda</sub> = 0.0. This table was created by the HEASARC in October 2004 based on CDS tables J/A+A/425/367/reflex70.dat and J/A+A/425/367/reflex.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/rosnepagn
- Title:
- ROSAT North Ecliptic Pole Survey Active Galactic Nuclei Catalog
- Short Name:
- ROSATNEPAGN
- Date:
- 10 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The ROSAT North Ecliptic Pole (NEP) Survey of Active Galactic Nuclei (AGN) Catalog is an X-ray flux-limited sample of 219 AGN discovered in the contiguous 80.7 square degrees region of the ROSAT North Ecliptic Pole (NEP) Survey (Gioia et al. 2003, ApJS, 149, 29; CDS Cat. <J/ApJS/149/29>). This catalog features complete optical identifications and spectroscopic redshifts. The median redshift, X-ray flux, and X-ray luminosity are z = 0.41, fx = 1.1 x 10<sup>-13</sup> erg/cm<sup>2</sup>/s, and Lx = 9.2 x 10<sup>43</sup> h70<sup>-2</sup> erg/s (0.5 - 2.0 keV), respectively. Unobscured Type 1 AGN are the dominant constituents (90%) of this soft X-ray-selected sample of AGN. This catalog sample includes several notable revisions relative to previous versions of the catalog (Mullis 2001, Ph. D. thesis, U. Hawaii; Gioia et al. 2003, ApJS, 149, 29, available in HEASARC Browse as the ROSNEPOID table). Firstly, the AGN fluxes and luminosities previously reported were overestimated by approximately 20% on average as a result of an error in the conversion of X-ray count rate to flux. Secondly, the sample has grown by 1 because of the reclassification of one of the X-ray sources (RX J1824.7+6509). Finally, in the present study the authors have adopted the presently favored "concordance" cosmology in computing the X-ray luminosities. The revised and updated catalog with corrected properties presented here should be the reference point for any future work with the ROSAT NEP AGN sample. This table was created by the HEASARC in August 2005 based on CDS table J/ApJ/617/192/table1.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/rosgalclus
- Title:
- ROSAT PSPC Catalog of Clusters of Galaxies
- Short Name:
- ROSAT/Clust.
- Date:
- 10 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This is a catalog of 203 clusters of galaxies serendipitously detected in 647 ROSAT PSPC high Galactic latitude pointings covering 158 square degrees. This is one of the largest X-ray-selected cluster samples, comparable in size only to the ROSAT All-Sky Survey sample of nearby clusters (Ebeling et al. 1997). Clusters in the inner 17.'5 of the ROSAT PSPC field of view are detected using the spatial extent of their X-ray emission. Fluxes of detected clusters range from 1.6 x 10^-14 to 8 x 10^-12 ergs s^-1 cm^-2 in the 0.5-2 keV energy band. X-ray luminosities range from 10^42 ergs s^-1, corresponding to very poor groups, to ~5 x 10^44 ergs s^-1, corresponding to rich clusters. The cluster redshifts range from z = 0.015 to z > 0.5. The catalog lists X-ray fluxes, core radii, and spectroscopic redshifts for 73 clusters and photometric redshifts for the remainder. Of 223 X-ray sources, 203 have been optically confirmed as clusters of galaxies. Of the remaining 20 sources, 19 are likely false detections arising from blends of unresolved point X-ray sources. Optical identifications of the remaining object are hampered by a nearby bright star. Above a flux of 2 x 10^-13 ergs s^-1 cm^-2, 98% of extended X-ray sources are optically confirmed clusters. The number of false detections and their flux distribution are in perfect agreement with simulations. The log N-log S relation for clusters derived from this catalog shows excellent agreement with counts of bright clusters derived from the Einstein Extended Medium Sensitivity Survey and the ROSAT All-Sky Survey. At fainter fluxes, its log N-log S relation agrees with the smaller area WARPS survey. The cluster counts appear to be systematically higher than those from a 50 square degree survey by Rosati et al. This database was created by the HEASARC in December 2001 based on the CDS/ADC catalog J/ApJ/502/558/ (table3.dat). This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/rosatrqq
- Title:
- ROSAT Radio-Quiet Quasars Catalog
- Short Name:
- ROSAT/RQQ
- Date:
- 10 May 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/roxa
- Title:
- ROXA (Radio-Optical-X-ray at ASDC) Blazars Catalog
- Short Name:
- ROXA
- Date:
- 10 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- Although blazars are a small fraction of the overall AGN population, they are expected to be the dominant population of extragalactic sources in the hard X-ray and gamma-ray bands and have been shown to be the largest contaminant of CMB fluctuation maps. So far the number of known blazars is of the order of several hundreds, but the forthcoming AGILE, GLAST and Planck space observatories will detect several thousand of objects of this type. In preparation for these missions it is necessary to identify new samples of blazars to study their multi-frequency characteristics and statistical properties. The authors have compiled a sample of objects with blazar-like properties via a cross-correlation between large radio (NVSS, ATCAPMN) and X-ray surveys (RASS) using the SDSS-DR4 and 2dF survey data to spectroscopically identify their candidates and test the validity of the selection method. They present the Radio-Optical-X-ray catalog built at ASDC (ROXA), a list of 816 objects among which 510 are confirmed blazars. Only 19% of the candidates turned out to be certainly non-blazars, demonstrating the high efficiency of our selection method. This catalog includes 173 new blazar identifications, or about 10% of all presently known blazars. The relatively high flux threshold in the X-ray energy band (given by the RASS survey) preferentially selects objects with high F_X/F_r ratio, leading to the discovery of new High Energy Peaked BL Lac (HBLs). This catalog therefore includes many new potential targets for GeV-TeV observations. The selection method consisted of three steps: 1) a first cross-correlation between radio and X-ray surveys (the NRAO VLA Sky Survey, ATCAPMN (ATCA catalogue of compact PMN sources) and ROSAT All Sky Survey; 2) for each radio/X-ray match, optical magnitudes were retrieved from the Guide Star Catalog; 3) for all radio/optical/X-ray matches the authors calculated the X-ray to optical (alpha_ox) and radio to optical (alpha_ro) spectral slopes and took only sources with alpha_ox and alpha_ro values within the blazar area. For each object, redshift, B and G magnitudes, radio fluxes at 1.4 GHz and at 5 GHz, X-ray flux, F_X/F_r ratio, X-ray luminosity, radio luminosity, Ca H&K break and classification are given. This table was created by the HEASARC in November 2007 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/472/699">CDS catalog J/A+A/472/699</a> file catalog.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/sdssnbckde
- Title:
- SDSS NBCKDE Catalog of Photometrically Selected Quasar Candidates
- Short Name:
- SDSSNBCKDE
- Date:
- 10 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains a catalog of 1,015,082 quasar candidates selected from the photometric imaging data of the Sloan Digital Sky Survey (SDSS) using a non-parametric Bayesian classification kernel density estimator (NBC-KDE). It excludes 157,075 initial candidates that were culled as known or likely contaminants. The objects are all point sources to a limiting magnitude of i = 21.3 from 8417 deg<sup>2</sup> of imaging from SDSS Data Release 6 (DR6). This sample extends the previous catalog (Paper I: Richards et al. 2004, ApJS, 155, 257) by using the latest SDSS public release data and probing both ultraviolet (UV)-excess and high-redshift quasars. While the addition of high-redshift candidates reduces the overall efficiency (quasars:quasar candidates) of the catalog to ~80%, it is expected to contain no fewer than 850,000 bona fide quasars, which is ~8 times the number of the previous sample and ~10 times the size of the largest spectroscopic quasar catalog. Cross-matching between this photometric catalog and spectroscopic quasar catalogs from both the SDSS and 2dF survey yields 88,879 spectroscopically confirmed quasars. For judicious selection of the most robust UV-excess sources (~500,000 objects in all), the efficiency is nearly 97 - more than sufficient for detailed statistical analyses. The catalog's completeness to type 1 (broad-line) quasars is expected to be no worse than 70%, with most missing objects occurring at z < 0.7 and 2.5 < z < 3.0. In addition to classification information, the authors provide photometric redshift estimates (typically good to Delta(z) +/- 0.3 [2-sigma]) and cross-matching with radio, X-ray, and proper-motion catalogs. Finally, the authors have considered the catalog's utility for determining the optical luminosity function of quasars and are able to confirm the flattening of the bright-end slope of the quasar luminosity function at z ~ 4 as compared to z ~ 2. 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 based on an electronic version of Table 1 in the reference paper which was obtained from the ApJ web site. This is a service provided by NASA HEASARC .