- ID:
- ivo://nasa.heasarc/eingalclus
- Title:
- Einstein Observatory Clusters of Galaxies Catalog
- Short Name:
- Einstein/Clus
- Date:
- 18 Apr 2025
- 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 .
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- ID:
- ivo://nasa.heasarc/einstein2e
- Title:
- Einstein Observatory 2E Catalog of IPC X-Ray Sources
- Short Name:
- Einstein2E
- Date:
- 18 Apr 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This is the Einstein Observatory 2E Catalog of Imaging Proportional Counter (IPC) X-Ray Sources which was created by the HEASARC from the CDS Catalog IX/13. This latter catalog was prepared by the CDS in October 1996 based on the Einline version. It is similar to the HEASARC's IPC source catalog which the HEASARC created in the early 1990s directly based on Einstein Observatory Source Catalog tables obtained from the then-extant Astrophysics Data System distributed data archive. The IPC Catalog contains 6816 entries compared to 5948 entries in this catalog, notice. This catalog contains sources with signal-to-noise values of 3.5 and greater from Einstein IPC observations. Note that a single source may have more than one entry in this catalog. This catalog was created by the HEASARC in November 2000 based on the <a href="https://cdsarc.cds.unistra.fr/ftp/cats/IX/13">CDS Catalog IX/13</a> file 2e.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/sssraw
- Title:
- Einstein SSS and MPC Raw Data
- Short Name:
- SSSRAW
- Date:
- 18 Apr 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The Einstein Observatory (also known as HEAO-2 or HEAO-B) was operational from 1978 November 13 until 1981 April 25 when the attitude control system failed. The Solid State Spectrometer (SSS) was operated intermittently between 1978 December 1 and 1979 October 22. However, the cryogen cooling for the detector was used up by about 2 weeks prior to the date of this last observation, so that the last reliable observation of the SSS is considered to have occurred on 1979 October 03. The SSSRAW database accesses the raw SSS data (and the associated monitoring proportional counter, MPC, data), restored in FITS format at HEASARC from the original machine dependent format data set. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/sss
- Title:
- Einstein SSS Spectra and Lightcurves
- Short Name:
- SSS
- Date:
- 18 Apr 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table is the Einstein Solid State Spectrometer catalog of observations and data products. It incorporates the most recent ice model that is described in the article on the SSS calibration by Christian, Swank, and White that appeared in the HEASARC journal, Legacy, No. 1. Also available as "associated" data products are the quasi-simultaneous observations made by the Einstein Monitor Proportional Counter. There are 634 distinct SSS observations in this database, 95% of which have associated MPC data products. The remaining SSS observations cover time intervals in which all MPC data was flagged as bad by the pCHIP program that was used to generate the MPC spectra and lightcurves. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/einopslgal
- Title:
- Einstein Survey of Optically Selected Galaxies
- Short Name:
- Einstein/OGal
- Date:
- 18 Apr 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The Einstein Survey of Optically Selected Galaxies contains the results of a complete Einstein Imaging Proportional Counter (IPC) X-ray survey of optically-selected galaxies from the Shapley-Ames (S-A) Catalog (CDS Catalog <VII/112>), the Uppsala General Catalog (UGC, <a href="https://cdsarc.cds.unistra.fr/ftp/cats/VII/26">CDS Catalog <VII/26></a>) and the European Southern Observatory (ESO) Catalog (<a href="https://cdsarc.cds.unistra.fr/ftp/cats/VII/115">CDS Catalog <VII/115></a>). Well-defined optical criteria were used to select the galaxies, and X-ray fluxes were measured at the optically-defined positions. The result is a comprehensive list of X-ray detection and upper limit measurements for 1018 galaxies. Of these, 827 galaxies have either independent distance estimates or radial velocities. Associated optical, redshift, and distance data have been assembled for these galaxies, and their distances come from a combination of directly predicted distances and those predicted from the Faber-Burstein Great Attractor/Virgocentric infall model. The accuracy of the X-ray fluxes has been checked in three different ways; all are consistent with the derived X-ray fluxes being of <= 0.1 dex accuracy. In particular, there is agreement with previously published X-ray fluxes for galaxies in common with a 1991 study by Roberts et al. (1991ApJS...75..751R) and a 1992 study by Fabbiano et al. (1992ApJS...80..531F, also available at the HEASARC as a database table called EINGALCAT). This database was created at the HEASARC in May 2002 based on the ADC/<a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/ApJS/111/163">CDS Catalog J/ApJS/111/163</a> and is derived from Tables 5, 6, 7, 12, 13, and 14 of the published paper. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/twosigma
- Title:
- Einstein Two-Sigma Catalog
- Short Name:
- Einstein/ETS
- Date:
- 18 Apr 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The X-ray sources from observations made with the Einstein Observatory (HEAO-2) Imaging Proportional Counter (IPC) that have intensities of 2-sigma or more above the background are compiled in this catalog. This catalog covers more sky at fainter flux levels than the Einstein Medium Sensitivity Survey. Fields with diffuse emission sources such as bright Abell clusters of galaxies and supernova remnants were excluded. Thus, data within 10 degrees of the galactic plane as well as fields within the boundaries of the Magellanic Clouds were excluded. Regions crowded with galactic sources such as the Orion and Pleiades fiels were also excluded. Excluding redundant fields, this catalog covers 1850 sq. degrees of the sky. The generation of the Einstein Two-Sigma Catalog was described in detail by Moran et al. (1996). Please read this article carefully to ensure responsible use of the Catalog. Detailed scientific and technical questions on the contents and methodology of this catalog should be addressed to the first author, Ed Moran (edhed@igpp.llnl.gov). In particular, it should be noted that, by design, this catalog contains a significant number of spurious sources: only 28%, or about 13,000 sources, out of the 46,000 source in the 2-sigma catalog are `real` astrophysical sources, with the remainder of the sources being spurious ones. Moran et al. show in their paper that performing cross-correlations of 2-sigma sources with other catalogs is an effective way of selecting sources in this catalog that are probably real. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/elaiscxo
- Title:
- ELAIS N1 and N2 Fields Chandra X-Ray Point Source Catalog
- Short Name:
- ELAISCXO
- Date:
- 18 Apr 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains the results of an analysis of two deep (75 ks) Chandra observations of the European Large Area Infrared Space Observatory (ISO) Survey (ELAIS) fields N1 and N2 as the first results from the ELAIS deep X-ray survey. This survey is being conducted in well-studied regions with extensive multiwavelength coverage. This table contains the Chandra source catalogs along with an analysis of source counts and hardness ratios. A total of 233 X-ray point sources were detected in addition to two soft extended sources (not included in this table of point sources), which are found to be associated with galaxy clusters. An overdensity of sources is found in N1 with 30 per cent more sources than N2, which the authors attribute to large-scale structure. A similar variance is seen between other deep Chandra surveys. The source count statistics reveal an increasing fraction of hard sources at fainter fluxes. The number of galaxy-like counterparts also increases dramatically towards fainter fluxes, consistent with the emergence of a large population of obscured sources. The ELAIS Deep X-ray Survey (EDXS) is being conducted in the northern ELAIS regions N1 and N2. The Chandra data consist of approximately 75 ks exposures in each field. Region N1 was observed on 2000 August 3-4 (Obs_ID 888) and N2 on 2000 August 2-3 (Obs_ID 887). The nominal aimpoints were 16:10:20.11 +54:33:22.3 for N1, and 16:36:46.99 +41:01:33.7 for N2 in J2000.0 coordinates. The ACIS-I chips were used with the addition of the ACIS-S2 and ACIS-S4 chips. This table was created by the HEASARC in February 2007 based on the <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/MNRAS/343/293">CDS catalog J/MNRAS/343/293</a> files table1.dat and table2.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/elaiss1xmm
- Title:
- ELAIS S1 Field XMM-Newton X-Ray Source Catalog
- Short Name:
- ELAISS1XMM
- Date:
- 18 Apr 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The formation and evolution of cosmic structures can be probed by studying the evolution of the luminosity function of the Active Galactic Nuclei (AGNs), galaxies and clusters of galaxies and of the clustering of the X-ray active Universe, compared to the IR-UV active Universe. To this purpose, the authors have surveyed with XMM-Newton the central ~0.6 deg<sup>2</sup> region of the ELAIS-S1 field down to flux limits of ~5.5 x 10<sup>-16</sup> erg cm<sup>-2</sup> s<sup>-1</sup> (0.5-2 keV, soft band, S), ~2 x 10<sup>-15</sup> erg cm<sup>-2</sup> s<sup>-1</sup> (2-10 keV, hard band, H), and ~4 x 10<sup>-15</sup> erg cm<sup>-2</sup> s<sup>-1</sup> (5-10 keV, ultra-hard band, HH). They present here the analysis of the XMM-Newton observations, the number counts in different energy bands and the clustering properties of the X-ray sources. They have detected a total of 478 sources, 395 and 205 of which detected in the S and H bands respectively. They identified 7 clearly extended sources and estimated their redshift through X-ray spectral fits with thermal models. In four cases the redshift is consistent with z = 0.4, so they may have detected a large scale structure formed by groups and clusters of galaxies through their hot intra-cluster gas emission. The relative density of the S band sources is higher near the clusters and groups at z ~ 0.4 and extends toward East and the South/West. This suggests that the structure is complex, with a size comparable to the full XMM-Newton field. Conversely, the highest relative source densities of the H band sources are located in the central-west region of the field. The mosaic of four partially overlapping deep XMM-Newton pointings covers a large (~0.6 deg<sup>2</sup>) and contiguous area of the ELAIS-S1 region. The pointings are named <pre> ELAIS-S1-A (RA=8.91912, DE=-43.31344, J2000), ELAIS-S1-B (RA=8.92154, DE=-43.65575, J2000), ELAIS-S1-C (RA=8.42195, DE=-43.30488, J2000) and ELAIS-S1-D (RA=8.42375, DE=-43.65327, J2000). </pre> The X-ray observations were performed on May 2003 through July 2003 with XMM-Newton's European Photon Imaging Camera (EPIC) and two MOS-CCD cameras. This table was created by the HEASARC in June 2008 based on the <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/457/501">CDS Catalog J/A+A/457/501</a> files elaisxmm.dat and catalog.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/elaiss1oid
- Title:
- ELAIS S1 Field X-Ray Source Optical/IR Identifications Catalog
- Short Name:
- ELAISS1OID
- Date:
- 18 Apr 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains the optical identifications and a multi-band catalog of a sample of 478 X-ray sources detected in the XMM-Newton and Chandra surveys of the central 0.6 deg<sup>2</sup> of the ELAIS-S1 field. The most likely optical/infrared counterpart of each X-ray source was identified using the chance coincidence probability in the R and IRAC 3.6 micron bands.This method was complemented by the precise positions obtained through Chandra observations. The authors were able to associate a counterpart to each X-ray source in the catalogue. Approximately 94% of them are detected in the R band, while the remaining are blank fields in the optical down to R ~ 24.5, but have a near-infrared counterpart detected by IRAC within 6 arcsec of the XMM-Newton centroid. The multi-band catalog, produced using the positions of the identified optical counterparts, contains photometry in ten photometric bands, from B to the MIPS 24 micron band. The spectroscopic follow-up allowed us to determine the redshift and classification for 237 sources (~ 50% of the sample) brighter than R = 24. The spectroscopic redshifts were complemented by reliable photometric redshifts for 68 sources. The authors classified 47% of the sources with spectroscopic redshift as broad-line active galactic nuclei (BL AGNs) with z = 0.1-3.5, while sources without broad-lines (NOT BL AGNs) are about 46% of the spectroscopic sample and are found up to z = 2.6. The remaining fraction is represented by extended X-ray sources and stars. The authors spectroscopically identified 11 type 2 QSOs among the sources with F(2-10 keV)/F(R) > 8, with redshift between 0.9 and 2.6, high 2-10 keV luminosity (log L(2-10 keV) >= 43.8 erg/s) and hard X-ray colors suggesting large absorbing columns at the rest frame (log N<sub>H</sub> up to 23.6 cm<sup>-2</sup>). BL AGNs show on average blue optical-to-near-infrared colors, softer X-ray colors and X-ray-to-optical colors typical of optically selected AGNs. Conversely, narrow-line sources show redder optical colors, harder X-ray flux ratio and span a wider range of X-ray-to-optical colors. On average the Spectral Energy Distributions (SEDs) of high-luminosity BL AGNs resemble the power-law typical of unobscured AGNs. The SEDs of NOT BLAGNs are dominated by the galaxy emission in the optical/near-infrared, and show a rise in the mid-infrared which suggests the presence of an obscured active nucleus. The authors have used the infrared-to-optical colors and near-infrared SEDs to infer the properties of the AGN host galaxies. Identifications and photometric parameters for 478 sources detected by XMM-Newton in the ELAIS-S1 field are given. For each source, the X-ray positions and fluxes, optical position and photometry, Spitzer IRAC and MIPS 24 micron positions and fluxes, spectroscopic redshift where available, photometric redshift and SED shape classification are given. This table was created by the HEASARC in December 2008 based on the <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/488/417">CDS Catalog J/A+A/488/417</a> file catalog.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/xmmvaragn
- Title:
- Ensemble X-Ray Variability of AGN in 2XMMi-DR3
- Short Name:
- XMMVARAGN
- Date:
- 18 Apr 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The X-ray variability of active galactic nuclei (AGN) has been most often investigated with studies of individual, nearby sources, and only a few ensemble analyses have been applied to large samples in wide ranges of luminosity and redshift. In their study, the authors aimed to determine the ensemble variability properties of two serendipitously selected AGN samples extracted from the catalogs of XMM-Newton and Swift (the latter is not included in this table, notice), with redshift between ~ 0.2 and ~ 4.5, and X-ray luminosities, in the 0.5 - 4.5 keV band, between ~ 10<sup>43</sup> erg/s and ~ 10<sup>46</sup> erg/s. They used the structure function (SF), which operates in the time domain, and allows for an ensemble analysis even when only a few observations are available for individual sources and the power spectral density (PSD) cannot be derived. The SF is also more appropriate than fractional variability and excess variance, because these parameters are biased by the duration of the monitoring time interval in the rest-frame, and therefore by cosmological time dilation. The authors find statistically consistent results for the two samples, with the SF described by a power law of the time lag tau, approximately as SF ~ tau<sup>0.1</sup>. They do not find evidence of the break in the SF, at variance with the case of lower luminosity AGNs. They confirm a strong anti-correlation of the variability with X-ray luminosity, accompanied by a change of the slope of the SF. They also find evidence in support of a weak, intrinsic, average increase of X-ray variability with redshift. For XMM, the authors used the version of the Serendipitous Source Catalog then available, namely 2XMMi-DR3, the latest incremental update of the second version of the catalogue, with observations made between 2000 February 3 and 2008 October 08; all datasets were publicly available by 2009 October 31, but not all public observations are included in this catalog. The total area of the catalog fields is ~ 814 deg<sup>2</sup>, but taking account of the substantial overlaps between observations, the net sky area covered independently is ~ 504 deg<sup>2</sup>. The 2XMMi-DR3 catalogue contains 353,191 detections (above the processing likelihood threshold of 6), related to 262,902 unique X-ray sources, therefore a significant number of sources (41,979) have more than one record within the catalog. The selected sources were cross-correlated with the DR7 edition of the SDSS Quasar Catalog (Schneider et al. 2010, AJ, 139, 2360) to obtain redshifts and spectral classifications for the sources. The authors used a maximum distance of 1.5 arcseconds, corresponding to the uncertainty in the X-ray positions, resulting in 412 quasars that were observed by XMM-Newton from 2 to 25 epochs each for a total of 1376 observations. The authors refer to these sources as the XMM-Newton sample. This table was created by the HEASARC in April 2012 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/536/A84">CDS Catalog J/A+A/536/A84</a> file table1.dat. This is a service provided by NASA HEASARC .
