- ID:
- ivo://nasa.heasarc/rassvars
- Title:
- RASS X-Ray Variable Sources Catalog
- Short Name:
- ROSAT/Vars
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The RASS X-Ray Variable Sources Catalog contains the results of a systematic search for variability among the ROSAT All-Sky Survey (RASS) X-ray sources. Lightcurves were generated for about 30,000 X-ray point sources which were detected sufficiently high above the background. For the variability study different search algorithms were developed in order to recognize flares, periods and trends, respectively. The variable X-ray sources were optically identified with counterparts in the SIMBAD, the USNO-A2.0 and NED data bases, but a significant part of the X-ray sources remain without cataloged optical counterparts. A complete list of the 1207 X-ray variable sources that were found is presented in this table. This table was created by the HEASARC in July 2003 based on CDS table J/A+A/403/247/table7.dat. This is a service provided by NASA HEASARC .
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Search Results
- ID:
- ivo://CDS.VizieR/J/A+AS/146/323
- Title:
- RASS young sources around R CrA
- Short Name:
- J/A+AS/146/323
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the ROSAT All-Sky Survey data in a 126 deg^2^ area in and around the CrA star forming region. With low-resolution spectroscopy of unidentified ROSAT sources we could find 19 new pre-main sequence stars, two of which are classical T Tauri stars, the others being weak-lined. The spectral types of these new T Tauri stars range from F7 to M6. The two new classical T Tauri stars are located towards two small cloud-lets outside of the main CrA cloud. They appear to be ~10 Myrs old, by comparing their location in the H-R diagram with isochrones for an assumed distance of 130 pc, the distance of the main CrA dark cloud. The new off-cloud weak-line T Tauri stars may have formed in similar cloudlets, which have dispersed recently. High-resolution spectra of our new T Tauri stars show that they have significantly more lithium absorption than zero-age main-sequence stars of the same spectral type, so that they are indeed young. From those spectra we also obtained rotational and radial velocities. For some stars we found the proper motion in published catalogs. The direction and velocity of the 3D space motion - south relative to the galactic plane - of the CrA T Tauri stars is consistent with the dark cloud being formed originally by a high-velocity cloud impact onto the galactic plane, which triggered the star formation in CrA. We also present VRIJHK photometry for most of the new T Tauri stars to derive their luminosities, ages, and masses.
- ID:
- ivo://CDS.VizieR/J/MNRAS/311/456
- Title:
- RIXOS source catalogue
- Short Name:
- J/MNRAS/311/456
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We describe the ROSAT International X-ray/Optical Survey (RIXOS), a medium-sensitivity survey and optical identification of X-ray sources discovered in ROSAT high Galactic latitude fields (|b|>280) and observed with the Position Sensitive Proportional Counter (PSPC) detector. We presents a catalogue of the RIXOS sources and their optical identifications.
- ID:
- ivo://CDS.VizieR/J/A+AS/122/235
- Title:
- ROSAT active galaxies identifications
- Short Name:
- J/A+AS/122/235
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Table 2 gives the 5 GHz high resolution radio source properties for the 1861 Rosat-GreenBank (RGB) sources for which subarcsecond positions and core radio flux densities were obtained. After submission of this paper, we discovered a possible systematic position error in a very small subset of sources. In particular, the sources RGB J0131+005, RGB J0139+178, RGB J0143+129, RGB J0157+235A, RGB J0232+202, RGB J0233+024A, RGB J0243+171, RGB J0256+035, RGB J0303+059, RGB J0308+104, RGB J0312+243A, RGB J0312+242C, and RGB J0314+063 were all observed in our "c" epoch VLA runs and show large systematic offsets with respect to sources found in the NVSS survey. We re-examined these sources and found the position reported in the tables is accurate given our data, but that the noise on these fields before any CLEANing is abnormally high. We thank Dr. Alastair Edge for pointing out this discrepancy. Table 3 gives the 5 GHz radio source properties for the 436 Rosat-Green Bank (RGB) sources for which only low resolution data were obtained. Table 4 gives the 83 Rosat-Green Bank (RGB) sources for which no radio source greater than 5 sigma was observed in the follow-up VLA observations. These catalogs consist of radio- and X-ray-loud AGN selected from a correlation of the 1987 Green Bank radio catalog and the Rosat All-Sky Survey.
- ID:
- ivo://CDS.VizieR/J/A+AS/109/147
- Title:
- ROSAT AGN content
- Short Name:
- J/A+AS/109/147
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The cross-correlation of the source list from the ROSAT All-Sky Survey with the 5 GHz Green Bank survey yields a list of 2127 objects. About two thirds of them are optically unidentified. The majority of the objects with known optical counterparts are quasars and radio galaxies, most of them detected in X-rays for the first time. In this paper we present a list of the previously optically identified objects with their main characteristics and discuss their general (bulk) properties. We find strong correlations between luminosities in the radio, optical, and X-ray bands which differ for quasars and radio galaxies.
- ID:
- ivo://CDS.VizieR/IX/10A
- Title:
- ROSAT All-Sky Bright Source Catalogue (1RXS)
- Short Name:
- IX/10A
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The ROSAT All-Sky Survey Bright Source Catalogue (RASS-BSC, revision 1RXS) is derived from the all-sky survey performed during the first half year (1990/91) of the ROSAT mission. 18,806 sources are catalogued (five sources were removed compared to the 18,811 sources of the 1996 version), down to a limiting ROSAT PSPC count-rate of 0.05cts/s in the 0.1-2.4keV energy band, with a detection likelihood of at least 15 and with at least 15 source photons. For 94% of the sources visual inspection confirmed the results of the standard processing with respect to existence and position; the remaining 6% were re-analysed and appropriately flagged. At a brightness limit of 0.1cts/s (8,547 sources) the catalogue represents a sky coverage of 92%. Broad band images are available for a subset of the flagged sources from http://www.rosat.mpe-garching.mpg.de/survey/rass-bsc . Questions or comments may be directed to <xray-info(at)mpe.mpg.de>
- ID:
- ivo://nasa.heasarc/rassdwarf
- Title:
- ROSAT All-Sky Survey: A-K Dwarfs/Subgiants
- Short Name:
- RASS/Dwarf
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This catalog presents X-ray data for all the main-sequence and subgiant stars of spectral types A, F, G, and K and luminosity classes IV and V listed in the Bright Star Catalogue (also known as the HR Catalogue) that have been detected as X-ray sources in the ROSAT All-Sky Survey (RASS). A number of stars in the appropriate spectral type range that do not have assigned luminosity classes have also been included. The catalogue contains 980 such HR stars detected as X-ray sources out of a total of 3054 stars in the HR Catalogue that satisfy the selection criteris, implying an average detection rate of 32%. In addition to the measured ROSAT PSPC count rates, source detection parameters, hardness ratios, and X-ray fluxes, X-ray luminosities derived from Hipparcos parallaxes are also listed. This database was created at the HEASARC in February 1999 based on the ADC/<a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+AS/132/155">CDS Catalog J/A+AS/132/155</a>. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/rassmaster
- Title:
- ROSAT All-Sky Survey Archival Data
- Short Name:
- RASSMASTER
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This database table contains the list German ROSAT All-Sky Survey observations which were obtained during the ROSAT All-Sky Survey phase (1990 July 30 to 1991 Jan 25) and which have become available to the public. These data were obtained in scanning mode and therefore an individual dataset covers a much larger area of the sky than do pointed moded observations. In addition all these data were obtained with PSPC-C, while all pointed mode observations after the end of the All-Sky Survey were obtained with PSPC-B. For each observation listed in this database table, the instrument used, processing site, and coordinates of the field center are given, as well as the ROSAT observation request number (ROR), actual exposure time, date the observation took place, and more. For details about the ROSAT instruments, consult the ROSAT Mission Description (NASA Research Announcement for ROSAT, Appendix F and its addendum) and the ROSAT GSFC GOF website at <a href="http://heasarc.gsfc.nasa.gov/docs/rosat/rosgof.html">http://heasarc.gsfc.nasa.gov/docs/rosat/rosgof.html</a> for more information. For more information about the ROSAT All Sky Survey, see the ROSAT All Sky Survey page at <a href="http://www.xray.mpe.mpg.de/cgi-bin/rosat/rosat-survey">http://www.xray.mpe.mpg.de/cgi-bin/rosat/rosat-survey</a>. This database table was created at the HEASARC in March 2002, based on information provided by Max-Planck-Institut fuer extraterrestrische Physik at <a href="http://wave.xray.mpe.mpg.de/">http://wave.xray.mpe.mpg.de/</a>. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/rassaeqso
- Title:
- ROSAT All-Sky Survey/ASIAGO-ESO QSO Survey Catalog
- Short Name:
- RASSAEQSO
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains some of the first results of a survey for bright quasars (V < 14.5 and R < 15.4) covering the northern hemisphere at Galactic latitudes |b| > 30 degrees. The photometric database is derived from the Guide Star and USNO catalogs. Quasars are identified on the basis of their X-ray emission measured in the ROSAT All-Sky Survey (RASS). The surface density of quasars brighter than 15.5 magnitudes turns out to be (10 +/- 2) x 10<sup>-3</sup> degrees<sup>-2</sup>, about 3 times higher than that estimated by the Palomar-Green (PG) survey. In the paper, the quasar optical luminosity function (LF) at 0.04 < z <= 0.3 is computed and shown to be consistent with a luminosity-dependent luminosity evolution of the type derived by La Franca & Cristiani (1997AJ....113.1517L) in the range 0.3 < z <=2.2. The predictions of semianalytical models of hierarchical structure formation agree remarkably well with the present observations. 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 reference paper which were obtained from the CDS (their catalog J/AJ/119/2540). 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:
- 07 Mar 2025
- 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 .
