- ID:
- ivo://CDS.VizieR/J/MNRAS/301/881
- Title:
- The ROSAT brightest cluster sample - I.
- Short Name:
- J/MNRAS/301/881
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a 90 per cent flux-complete sample of the 201 X-ray-brightest clusters of galaxies in the northern hemisphere ({delta}>=0{deg}), at high Galactic latitudes (|b|>= 20{deg}), with measured redshifts z<=0.3 and fluxes higher than 4.4x10^-12^erg/cm^2^/s in the 0.112.4 keV band. The sample, called the ROSAT Brightest Cluster Sample (BCS), is selected from ROSAT All-Sky Survey data and is the largest X-ray-selected cluster sample compiled to date. 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 are 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 per cent (mean 1{sigma} error).
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- ID:
- ivo://CDS.VizieR/J/MNRAS/341/1093
- Title:
- The Southern SHARC catalogue
- Short Name:
- J/MNRAS/341/1093
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Southern Serendipitous High-redshift Archival Cluster (SHARC) catalogue is a X-ray selected catalogue of galaxy clusters detected in deep ROSAT observations. The survey area is 17.7deg^2^ and is selected from long (greater than 10ks) ROSAT exposures with a declination <+20deg and excluding the Galactic plane (excluding galactic latitudes within the range [-20,20]deg). Optical follow-up was performed to confirm the presence of a galaxy cluster and measure its redshift. The final catalogue contains 32 galaxy clusters with redshifts between 0.05 and 0.70 and X-ray luminosities between 7x10^35^W and 4x10^37^W. Above a redshift of 0.3 - which forms the primary subsample of the survey - there are 16 clusters; the X-ray luminosities of these clusters are all greater than 2x10^36 W. All X-ray luminosities are quoted in the 0.5-2.0keV band and were calculated using an Einstein-de Sitter cosmology with H_0_ set to 50km/s/Mpc.
- ID:
- ivo://CDS.VizieR/IX/12
- Title:
- The WGACAT version of ROSAT sources
- Short Name:
- IX/12
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- WGACAT is a catalogue of point sources generated at HEASARC from all the ROSAT PSPC (Position Sensitive Proportional Counter) pointing observations from Feb 1991 to March 1994. These were the files available in the public archive at HEASARC as of September 1994. This catalog is an independent research effort aimed at releasing as quickly as possible a list of sources detected by ROSAT in its pointed phase to: (1) identify the detected sources, (2) ensure their timely observation by currently active X-ray missions e.g. ASCA, (3) to search for objects which show exceptional time variability and spectral properties and (4) to provide an independent check of the detection technique used in the official ROSAT project (SAS) processing. WGACAT stands for N.E. White (HEASARC/GSFC). P. Giommi (ESA), and L. Angelini (HEASARC/GSFC)
- ID:
- ivo://CDS.VizieR/IX/31
- Title:
- The WGACAT version of ROSAT sources
- Short Name:
- IX/31
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- WGACAT is a point source catalogue generated from all ROSAT PSPC (Position Sensitive Proportional Counter) pointed observations. This catalog has been generated by N.E. White (HEASARC/GSFC), P. Giommi (SDC/ASI) and L. Angelini (HEASARC/GSFC) and is a private research effort, not related to the official catalogs generated by the ROSAT project. The WGACAT was made first publicly available in November 1994 through the HEASARC on-line service (White, Giommi and Angelini 1994), with a first minor revision in March 1995 (WGACAT95). It was generated using all the public ROSAT PSPC pointed data available than, corresponding to 75% of the entire set, and featured ~ 68000 detections of which 62000 were unique sources. The current version, released in May 2000, is the final and complete version of WGACAT and includes the remaining sequences not processed in the WGACAT95. WGACAT (May 2000) contains about 88,000 detections, with more than 84,000 individual sources, obtained from 4160 sequences. The catalog was generated using an optimized sliding cell detect algorithm in XIMAGE (first developed for the EXOSAT project). The inner and outer parts of the images were run separately, to maximize the sensitivity to source detection. This method is very sensitive in finding point sources, but can also find spurious sources where there is extended emission. We have visually inspected each detection, removed the obvious spurious cases and assigned a quality flag to each detection.
- ID:
- ivo://CDS.VizieR/J/A+A/297/391
- Title:
- T Tauri stars ROSAT survey
- Short Name:
- J/A+A/297/391
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We study the X-ray emission of T Tauri stars (TTS) in Taurus-Auriga as observed with the spatially unbiased flux-limited ROSAT All-Sky Survey.
- ID:
- ivo://nasa.heasarc/warps
- Title:
- Wide Angle ROSAT Pointed Survey, First Phase (WARPS-I)
- Short Name:
- ROSAT/WARPS
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The Wide Angle ROSAT Pointed Survey, First Phase (WARPS-I) table is a catalog which contains optical identifications for objects found in a serendipitous survey of relatively deep, pointed ROSAT observations for clusters of galaxies. The X-ray source detection algorithm used by WARPS is Voronoi Tessellation and Percolation (VTP), a technique which is equally sensitive to point sources and to extended sources of low surface brightness. WARPS-I is based on the central regions of 86 ROSAT PSPC fields, covering an area of 16.2 square degrees. The X-ray source screening and optical identification process for WARPS-I yielded 34 clusters at 0.06<z<0.75. Twenty-two of these clusters form a complete, statistically well-defined sample drawn from 75 of these 86 fields, covering an area of 14.1 square degrees, with a flux limit of F(0.5-2.0keV) = 6.5x10<sup>-14</sup> erg/cm<sup>2</sup>/s. This sample can be used to study the properties and evolution of the gas, galaxy and dark matter content of clusters and to constrain cosmological parameters. This online catalog was created by the HEASARC in May 2003 based on machine-readable versions of tables 2, 3, 4 and 5 of Perlman et al. (2002) that were obtained from the CDS. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/warps2
- Title:
- Wide Angle ROSAT Pointed Survey, Second Phase (WARPS-II) Clusters Catalog
- Short Name:
- WARPS2
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains the galaxy cluster catalog from the second, larger phase of the Wide Angle ROSAT Pointed Survey (WARPS), an X-ray selected survey for high-redshift galaxy clusters. WARPS is among the largest deep X-ray cluster surveys and is being used to study the properties and evolution of galaxy clusters. The WARPS-II sample contains 125 clusters serendipitously detected in a survey of 301 ROSAT PSPC pointed observations and covers a sky area of 56.7 deg<sup>2</sup>. Of these 125 clusters, 53 have not been previously reported in the literature. The authors have nearly complete spectroscopic follow-up of the clusters, which range in redshift from z = 0.029 to z = 0.92 with a median redshift of z = 0.29 and they find 59 clusters with z >= 0.3 (29 not previously reported in the literature) and 11 clusters with z >= 0.6 (6 not previously reported). They also define a statistically complete subsample of 102 clusters above a uniform flux limit of 6.5 x 10<sup>-14</sup> ergs/cm<sup>2</sup>/s (0.5 - 2.0 keV). In their paper, the authors also compare their redshifts, fluxes, and detection methods to other similar published cluster surveys and state that they find no serious issues with their measurements or completeness. The list of ROSAT pointings used in WARPS-II is given in Table 1 of the first reference paper. The WARPS-I cluster catalog (the second reference listed below) is also available in Browse as the WARPS table. This table was created by the HEASARC in September 2010 based on the combination of the electronic versions of Tables 2, 3, and 4 from the first reference paper which were obtained from the CDS (their catalog J/ApJS/176/374). This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/w2ragncat
- Title:
- WISE/2MASS/RASS (W2R) AGN Sample Catalog
- Short Name:
- W2RAGNCAT
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The authors of this catalog have developed the S<sub>IX</sub> statistic to identify bright, highly likely active galactic nucleus (AGN) candidates solely on the basis of Wide-field Infrared Survey Explorer (WISE), Two-Micron All-Sky Survey (2MASS), and ROSAT All-Sky Survey (RASS) data. This statistic was optimized with data from the preliminary WISE survey and the Sloan Digital Sky Survey, and tested with Lick 3 m Kast spectroscopy. The authors find that sources with S<sub>IX</sub> < 0 have a >~ 95% likelihood of being an AGN (defined in this paper as a Seyfert 1, quasar, or blazar). This statistic was then applied to the full WISE/2MASS/RASS dataset, including the final WISE data release, to yield the "W2R" sample of 4316 sources with S<sub>IX</sub> < 0. Only 2209 of these sources are currently in the Veron-Cetty and Veron (VCV) Catalog of spectroscopically confirmed AGNs, indicating that the W2R sample contains nearly 2000 new, relatively bright (J <~ 16) AGNs. The authors utilize the W2R sample to quantify biases and incompleteness in the VCV Catalog. They find that it is highly complete for bright (J < 14), northern AGNs, but the completeness drops below 50% for fainter, southern samples and for sources near the Galactic plane. This approach also led to the spectroscopic identification of 10 new AGNs in the Kepler field, more than doubling the number of AGNs being monitored by Kepler. The W2R sample contains better than 1 bright AGN every 10 deg<sup>2</sup>, permitting construction of AGN samples in any sufficiently large region of sky. This table contains the 4316 sources comprising the W2R sample. This table was created by the HEASARC in June 2012 based on an electronic version of Table 3 from the reference paper which was obtained from the ApJ website. This is a service provided by NASA HEASARC .
- ID:
- ivo://CDS.VizieR/J/A+A/350/805
- Title:
- X-ray selected ROSAT AGN spectra
- Short Name:
- J/A+A/350/805
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the emission line properties of a sample of 76 bright soft X-ray selected ROSAT Active Galactic Nuclei. All optical counterparts are Seyfert 1 galaxies with rather narrow permitted lines, strong optical FeII line blends, and weak forbidden lines. By selection, they also have steep soft X-ray spectra when compared with typical Seyfert 1 galaxies. We discuss possible origins of these peculiar trends employing detailed correlation analyses, including a Principal Component Analysis. The optical spectra are presented in the Appendix.
- ID:
- ivo://CDS.VizieR/J/A+A/319/18
- Title:
- X-ray sources <1 degree from Seyfert galaxies
- Short Name:
- J/A+A/319/18
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Archived PSPC observations of 26 Seyfert galaxies have been analyzed for bright X-ray sources out to the full extent of the field (< about 50'). Of all Seyferts known this represents a sample 88% complete to B_T_=10mag, 74% complete to 11mag and 50% complete to 12mag. Using the same reduction algorithm, 14 fields centered on stars at high galactic latitudes have been used as control fields. Excluding the two brightest Seyferts, a subset of 24 Seyferts with corrected apparent magnitude between 8.04<B^o,i^_T_<12.90mag show a minimum excess of 46 bright X-ray sources generally distributed between 10 and 25' from the target galaxy. The significances of association of these sources with the Seyferts in the median brightness range are as high as 7.4-sigma.
