- ID:
- ivo://nasa.heasarc/xmmssclwbd
- Title:
- XMM-Newton 2XMMi-DR3 Selected Source Detections Catalog
- Short Name:
- XMMSSCLWBD
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The authors have carried out a classification of 4,330 X-ray sources in the 2XMMi-DR3 catalog. The sources were selected under the requirement of being a point source with multiple XMM-Newton observations and at least one detection with a signal-to-noise ratio larger than 20. For about one-third of the sources, the authors are able to obtain reliable source types from the literature. They mostly correspond to various types of stars (611), active galactic nuclei (AGNs, 753), and compact object systems (138) containing white dwarfs, neutron stars, and stellar-mass black holes. The authors find that about 99% of stars can be separated from other source types based on their low X-ray-to-IR flux ratios and frequent X-ray flares. AGNs have remarkably similar X-ray spectra, with the power-law photon index centered around 1.91 +/- 0.31, and their 0.2-4.5 keV flux long-term variation factors have a median of 1.48, with 98.5% being less than 10. In contrast, 70% of compact object systems can be very soft or hard, highly variable in X-rays, and/or have very large X-ray-to-IR flux ratios, separating them from AGNs. Using these results, the authors derive a source type classification scheme to classify the other sources and find 644 candidate stars, 1,376 candidate AGNs, and 202 candidate compact object systems, whose false identification probabilities are estimated to be about 1%, 3%, and 18%, respectively. There are still 320 sources associated with nearby galaxies and 151 in the Galactic plane, which the authors expect to be mostly compact object systems or background AGNs. There are also 100 candidate ultraluminous X-ray sources. They are found to be much less variable than other accreting compact objects. This table contains the list of 19,637 detections of the 4,330 unique X-ray sources which comprise the authors' sample. The list of 4,330 unique X-ray sources and their classifications is also available as the HEASARC XMMSSCLWBS table. This table was created by the HEASARC in October 2012 based on an electronic version of Table 3 from the reference paper which was obtained from the ApJ web site. This is a service provided by NASA HEASARC .
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- ID:
- ivo://nasa.heasarc/hcgxrbs
- Title:
- X-Ray Observations of Compact Group Galaxies
- Short Name:
- HCGXRBS
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This catalog presents the study of a sample of 15 compact groups (CGs) observed with Chandra/ACIS, Swift/UVOT and Spitzer/IRAC-MIPS for which archival data exist, allowing the authors to obtain SFRs, stellar masses, sSFRs and X-ray fluxes and luminosities for individual, off-nuclear point sources, which they summed to obtain total X-ray luminosities originating in off-nuclear point sources in a galaxy. Details on the Swift and Spitzer observations and data for systems in this sample can be found in Tzanavaris et al. (2010ApJ...716..556T) and Lenkic et al. (2016MNRAS.459.2948L). For Chandra/ACIS observations, see Tzanavaris et al. (2014ApJS..212....9T) and Desjardins et al. (2013ApJ...763..121D; 2014ApJ...790..132D). The authors obtained total galaxy X-ray luminosities, L<sub>X</sub>, originating from individually detected point sources in a sample of 47 galaxies in 15 compact groups of galaxies (CGs). For the great majority of the galaxies, they found that the detected point sources most likely are local to their associated galaxy, and are thus extragalactic X-ray binaries (XRBs) or nuclear active galactic nuclei (AGNs). For spiral and irregular galaxies, they found that, after accounting for AGNs and nuclear sources, most CG galaxies are either within the +/- 1 sigma scatter of the Mineo et al. L<sub>X</sub>-star formation rate (SFR) correlation or have higher L<sub>X</sub> than predicted by this correlation for their SFR. These "excesses" may be due to low metallicities and high interaction levels. For elliptical and S0 galaxies, after accounting for AGNs and nuclear sources, most CG galaxies were found to be consistent with the Boroson et al. L<sub>X</sub>-stellar mass correlation for low-mass XRBs, with larger scatter, likely due to residual effects such as AGN activity or hot gas. Assuming non-nuclear sources are low- or high-mass XRBs, the authors used appropriate XRB luminosity functions to estimate the probability that stochastic effects can lead to such extreme L<sub>X</sub> values. They found that, although stochastic effects do not in general appear to be important, for some galaxies there is a significant probability that high L<sub>X</sub> values can be observed due to strong XRB variability. This table was created by the HEASARC in May 2019 based upon the <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/ApJ/817/95">CDS Catalog J/ApJ/817/95</a> file table3.dat This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/xteasscat
- Title:
- XTE All-Sky Slew Survey Catalog
- Short Name:
- XTEASSCAT
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The Rossi X-Ray Timing Explorer (RXTE) All-Sky Survey Slew Catalog contains the results of a serendipitous hard X-ray (3 - 20 keV), nearly all-sky (|b|>10 degrees) survey based on observations by RXTE's Proportional Counter Array (PCA) which were performed during satellite reorientations in the period 1996 - 2002. The survey is 80% (90%) complete to a 4-sigma limiting flux of ~1.8 (2.5)x10<sup>-11</sup> erg/s/cm<sup>2</sup> in the 3 - 20 keV band. The achieved sensitivity in the 3 - 8 keV and 8 - 20 keV subbands is similar to and an order of magnitude higher than that of the previously record HEAO-1 A1 and HEAO-1 A4 all-sky surveys, respectively. A combined 7 x 10<sup>3</sup> square degree area of the sky is sampled to flux levels below 10<sup>-11</sup> erg/s/cm<sup>2</sup> (3 - 20 keV). In total 294 sources are detected and localized to better than ~1 degree; 236 (80%) of these can be confidently associated with a known astrophysical object; 22 of these sources have multiple counterparts (17 have 2 counterparts and 5 have 3 counterparts) with which they have been identified, and as these are listed as separate entries, there are 321 entries in this table. 35 detected sources remain unidentified, although for 12 of these we report a likely soft X-ray counterpart from the ROSAT all-sky survey bright source catalog. Of the reliably identified sources, 63 have a local origin (Milky Way, LMC or SMC), 64 are clusters of galaxies and 100 are active galactic nuclei (AGN). The fact that the unidentified X-ray sources have hard spectra suggests that the majority of them are AGN, including highly obscured ones (hydrogen column density > 10<sup>23</sup> cm<sup>-2</sup>). This dataset enabled the authors to present for the first time a log N - log S diagram for extragalactic sources above 4 x 10<sup>-12</sup> erg/s/cm<sup>2</sup> at 8 - 20 keV. This database table was created by the HEASARC in May 2004 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/418/927">CDS Catalog J/A+A/418/927</a>. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/xteslew
- Title:
- XTE Archived Public Slew Data
- Short Name:
- XTESLEW
- Date:
- 07 Mar 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This database table is a catalog of all the RXTE slew observations and is based on information culled from the RXTE Data Archive's latest top-level FMI (FITS Master Index) file that is created when data products are made publicly available each week. ObsIDs listed in this table are available for download from <a href="https://heasarc.gsfc.nasa.gov/FTP/xte/data/archive/">https://heasarc.gsfc.nasa.gov/FTP/xte/data/archive/</a>. See the parameter 'data_loc' for the relative location of specific ObsIDs. The XTESLEW database table is updated automatically, usually on a weekly basis whenever the RXTE GOF updates the top-level FMI for the public data archive and notifies the HEASARC. This is a service provided by NASA HEASARC .
