- ID:
- ivo://CDS.VizieR/J/A+A/527/A126
- Title:
- 2XMMi/SDSS DR7 cross-correlation
- Short Name:
- J/A+A/527/A126
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Survey Science Centre of the XMM-Newton satellite released the first incremental version of the 2XMM catalogue in August 2008. Containing more than 220000 X-ray sources, the 2XMMi was at that time the largest catalogue of X-ray sources ever published and thus constitutes an unprecedented resource for studying the high-energy properties of various classes of X-ray emitters such as AGN and stars. Thanks to the high throughput of the EPIC cameras on board XMM-Newton accurate positions, fluxes, and hardness ratios are available for a substantial fraction of the X-ray detections. The advent of the 7th release of the Sloan Digital Sky Survey offers the opportunity to cross-match two major surveys and extend the spectral energy distribution of many 2XMMi sources towards the optical bands. This implies building extensive homogeneous samples with a statistically controlled rate of spurious matches and completeness. We here present a cross-matching algorithm based on the classical likelihood ratio estimator. The method developed has the advantage of providing true probabilities of identifications without resorting to heavy Monte-Carlo simulations.
Number of results to display per page
Search Results
- ID:
- ivo://CDS.VizieR/J/A+A/534/A120
- Title:
- 2XMMi/SDSS Galaxy Cluster Survey
- Short Name:
- J/A+A/534/A120
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalogue of X-ray selected galaxy clusters and groups as a first release of the 2XMMi/SDSS Galaxy Cluster Survey. The survey is a search for galaxy clusters detected serendipitously in observations with XMM-Newton in the footprint of the Sloan Digital Sky Survey (SDSS). The main aims of the survey are to identify new X-ray galaxy clusters, investigate their X-ray scaling relations, identify distant cluster candidates, and study the correlation of the X-ray and optical properties. In this paper, we describe the basic strategy to identify and characterize the X-ray cluster candidates that currently comprise 1180 objects selected from the second XMM-Newton serendipitous source catalogue (2XMMi-DR3). Cross-correlation of the initial catalogue with recently published optically selected SDSS galaxy cluster catalogues yields photometric redshifts for 275 objects. Of these, 182 clusters have at least one member with a spectroscopic redshift from existing public data (SDSS-DR8). We developed an automated method to reprocess the XMM-Newton X-ray observations, determine the optimum source extraction radius, generate source and background spectra, and derive the temperatures and luminosities of the optically confirmed clusters. Here we present the X-ray properties of the first cluster sample, which comprises 175 clusters, among which 139 objects are new X-ray discoveries while the others were previously known as X-ray sources. For each cluster, the catalogue provides: two identifiers, coordinates, temperature, flux [0.5-2]keV, luminosity [0.5-2]keV extracted from an optimum aperture, bolometric luminosity L500, total mass M500, radius R500, and the optical properties of the counterpart. The first cluster sample from the survey covers a wide range of redshifts from 0.09 to 0.61, bolometric luminosities L500=1.9x10^42^-1.2x10^45^erg/s, and masses M500=2.3x10^13^-4.9x10^14^M_{sun}_. We extend the relation between the X-ray bolometric luminosity L500 and the X-ray temperature towards significantly lower T and L and still find that the slope of the linear L-T relation is consistent with values published for high luminosities.
- ID:
- ivo://nasa.heasarc/xmmsdssgcs
- Title:
- 2XMMi/SDSS Galaxy Cluster Survey
- Short Name:
- XMMSDSSGCS
- Date:
- 14 Feb 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- The authors have compiled a sample of X-ray-selected galaxy groups and clusters from the XMM-Newton Serendipitous Source Catalog (2XMMi-DR3) with optical confirmation and redshift measurement from the Sloan Digital Sky Survey (SDSS). In their paper, they present an analysis of the X-ray properties of this new sample with particular emphasis on the X-ray luminosity-temperature (L<sub>X</sub> - T) relation. The X-ray cluster candidates were selected from the 2XMMi-DR3 catalog in the footprint of the SDSS-DR7. The authors developed a finding algorithm to search for overdensities of galaxies at the positions of the X-ray cluster candidates in the photometric redshift space and to measure the redshifts of the clusters from the SDSS data. For optically confirmed clusters with good quality X-ray data, they derived the X-ray flux, luminosity, and temperature from proper spectral fits, while the X-ray flux for clusters with low-quality X-ray data was obtained from the 2XMMi-DR3 catalogue. The detection algorithm provides the photometric redshift of 530 galaxy clusters. Of these, 310 clusters have a spectroscopic redshift for at least one member galaxy. About 75 percent of the optically confirmed cluster sample are newly discovered X-ray clusters. Moreover, 301 systems are known as optically selected clusters in the literature while the remainder are new discoveries in X-ray and optical bands. The optically confirmed cluster sample spans a wide redshift range 0.03 to 0.70 (median z = 0.32). In this paper, they present the catalog of X-ray-selected galaxy groups and clusters from the 2XMMi/SDSS galaxy cluster survey. The catalog has two subsamples: (i) a cluster sample comprising 345 objects with their X-ray spectroscopic temperature and flux from the spectral fitting; (these objects are identified by having values for the table_sample parameter of 1 in this HEASARC implementation of the catalog) and (ii) a cluster sample consisting of 185 systems with their X-ray flux from the 2XMMi-DR3 catalog, because their X-ray data are insufficient for spectral fitting (these objects are identified by having values for the table_sample parameter of 2 herein). For each cluster, the catalog also provides the X-ray bolometric luminosity and the cluster mass at R<sub>500</sub> based on scaling relations and the position of the likely brightest cluster galaxy (BCG). The updated L<sub>X</sub> - T relation of the current sample with X-ray spectroscopic parameters is presented in the paper. The authors found the slope of the L<sub>X</sub> - T relation to be consistent with published ones. They see no evidence for evolution in the slope and intrinsic scatter of the L<sub>X</sub> - T relation with redshift when excluding the low-luminosity groups. This catalog of X-ray selected galaxy clusters and groups supersedes and subsumes the first release of the 2XMMi/SDSS Galaxy Cluster Survey, comprising 175 clusters of galaxies, which was presented in Takey et al. (2011, A&A, 534, A120). This table was created by the HEASARC in October 2013 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/558/A75">CDS catalog J/A+A/558/A75</a> files table1.dat and table2.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://nasa.heasarc/xmmsdssgce
- Title:
- 2XMMi/SDSS Galaxy Cluster Survey Extension
- Short Name:
- XMMSDSSGCE
- Date:
- 14 Feb 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains results from the analysis of a sample of 383 X-ray selected galaxy groups and clusters with spectroscopic redshift measurements (up to z ~ 0.79) from the 2XMMi/SDSS Galaxy Cluster Survey. The X-ray cluster candidates were selected as serendipitously detected sources from the 2XMMi-DR3 catalog that were located in the footprint of the Sloan Digital Sky Survey (SDSS-DR7). The cluster galaxies with available spectroscopic redshifts were selected from the SDSS-DR10. The authors developed an algorithm for identifying the cluster candidates that are associated with spectroscopically targeted luminous red galaxies and for constraining the cluster spectroscopic redshift. A cross-correlation of the constructed cluster sample with published optically selected cluster catalogs yielded 264 systems with available redshifts. The present redshift measurements (presented in reference paper III) are consistent with the published values. The current cluster sample extends the optically confirmed cluster sample from the authors' cluster survey by 67 objects. Moreover, it provides spectroscopic confirmation for 78 clusters among their published cluster sample, which previously had only photometric redshifts. Of the new cluster sample that comprises 67 systems, 55 objects are newly X-ray discovered clusters and 52 systems are sources newly discovered as galaxy clusters in optical and X-ray wavelengths. Based on the measured redshifts and the fluxes given in the 2XMMi-DR3 catalogue, the authors have estimated the X-ray luminosities and masses of the cluster sample. This table contains 145 entries, 67 of which are new (as of Paper III) optically confirmed clusters (marked by values of ref_source = 'Paper III') and 78 of which are clusters from Paper II which have now been spectroscopically confirmed (marked by values of ref_source = 'Paper II'). The tabular information on the 530 clusters that was presented in Paper II of this set of papers is available as the HEASARC <a href="/W3Browse/xmm-newton/xmmsdssgcs.html">XMMSDSSGCS table</a>). The following parameters were obtained from the current optical-band cluster detection algorithm: sdss_dr10_bcg_id, sdss_dr10_bcg_ra, sdss_dr10_bcg_dec, bcg_rmag, redshift, num_spect_members, phot_redshift, num_phot_members, and spatial_offset. This table was created by the HEASARC in July 2014 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+A/564/A54">CDS catalog J/A+A/564/A54</a> file table1.dat. This is a service provided by NASA HEASARC .
- ID:
- ivo://CDS.VizieR/J/A+A/558/A75
- Title:
- 2XMMi/SDSS Galaxy Cluster Survey. II.
- Short Name:
- J/A+A/558/A75
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We compile a sample of X-ray-selected galaxy groups and clusters from the XMM-Newton serendipitous source catalogue (2XMMi-DR3) with optical confirmation and redshift measurement from the Sloan Digital Sky Survey (SDSS). The X-ray cluster candidates were selected from the 2XMMi-DR3 catalogue in the footprint of the SDSS-DR7. We developed a finding algorithm to search for overdensities of galaxies at the positions of the X-ray cluster candidates in the photometric redshift space and to measure the redshifts of the clusters from the SDSS data. The detection algorithm provides the photometric redshift of 530 galaxy clusters. Of these, 310 clusters have a spectroscopic redshift for at least one member galaxy. About 75 percent of the optically confirmed cluster sample are newly discovered X-ray clusters. Moreover, 301 systems are known as optically selected clusters in the literature while the remainder are new discoveries in X-ray and optical bands. The optically confirmed cluster sample spans a wide redshift range 0.03-0.70 (median z=0.32). In this paper, we present the catalogue of X-ray-selected galaxy groups and clusters from the 2XMMi/SDSS galaxy cluster survey. The catalogue has two subsamples: (i) a cluster sample comprising 345 objects with their X-ray spectroscopic temperature and flux from the spectral fitting, and (ii) a cluster sample consisting of 185 systems with their X-ray flux from the 2XMMi-DR3 catalogue, because their X-ray data are insufficient for spectral fitting. The updated L_X_-T relation of the current sample with X-ray spectroscopic parameters is presented. We see no evidence for evolution in the slope and intrinsic scatter of the L_X_-T relation with redshift when excluding the low-luminosity groups
- ID:
- ivo://CDS.VizieR/J/A+A/564/A54
- Title:
- 2XMMi/SDSS Galaxy Cluster Survey. III.
- Short Name:
- J/A+A/564/A54
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a sample of 383 X-ray selected galaxy groups and clusters with spectroscopic redshift measurements (up to z~0.79) from the 2XMMi/SDSS Galaxy Cluster Survey. The X-ray cluster candidates were selected as serendipitously detected sources from the 2XMMi-DR3 catalogue that were located in the footprint of the Sloan Digital Sky Survey (SDSS-DR7). The cluster galaxies with available spectroscopic redshifts were selected from the SDSS-DR10. We developed an algorithm for identifying the cluster candidates that are associated with spectroscopically targeted luminous red galaxies and for constraining the cluster spectroscopic redshift. A cross-correlation of the constructed cluster sample with published optically selected cluster catalogues yielded 264 systems with available redshifts. The present redshift measurements are consistent with the published values. The current cluster sample extends the optically confirmed cluster sample from our cluster survey by 67 objects. Moreover, it provides spectroscopic confirmation for 78 clusters among our published cluster sample, which previously had only photometric redshifts. Of the new cluster sample that comprises 67 systems, 55 objects are newly X-ray discovered clusters and 52 systems are sources newly discovered as galaxy clusters in optical and X-ray wavelengths. Based on the measured redshifts and the fluxes given in the 2XMMi-DR3 catalogue, we estimated the X-ray luminosities and masses of the cluster sample.
24527. XMM-LSS at 240MHz and 610MHz
- ID:
- ivo://CDS.VizieR/J/A+A/471/1105
- Title:
- XMM-LSS at 240MHz and 610MHz
- Short Name:
- J/A+A/471/1105
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The low-frequency radio survey of the XMM-Large Scale Structure (XMM-LSS) field aims to study the connection between the extragalactic radio source populations and their environment as traced by X-ray and optical emission. In this paper we present new radio observations of the XMM-LSS field carried out using the Giant Meterwave Radio Telescope at 240 and 610MHz. These observations complement the observations presented by Cohen at al. (2003, Cat. <J/ApJ/591/640>) and Tasse et al. (2006, Cat. <J/A+A/456/791>) at 74 and 325MHz with the Very Large Array. At 240 and 610MHz, we reach noise levels of ~2.5 and ~0.3mJy/beam, leading to the detection of 466 and 769 sources over 18.0 and 12.7 degree^2^ with resolutions of 14.7arcsec and 6.5arcsec respectively. Combining these data with the available source lists at 74, 325 (Tasse et al., 2006, Cat. <J/A+A/456/791>) and 1400MHz (NVSS), we build a multifrequency catalogue containing 1611 radio sources. We check for consistency of the astrometry and flux density estimates. We fit a simple synchrotron radiation model to the flux density measurements of the 318 radio sources being detected in at least 4 bands. While ~26% of them show signature of spectral ageing, ~6% show self absorption.
- ID:
- ivo://CDS.VizieR/J/MNRAS/382/279
- Title:
- XMM-LSS catalogue. Version I.
- Short Name:
- J/MNRAS/382/279
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We provide the source list for the first 5.5 surveyed square degrees of the XMM-LSS, with a total of 3385 point-like or extended sources above a detection likelihood of 15 in either 0.5-2 or 2-10keV bands. The table at CDS contains the main parameters, while further parameters and data products (X-ray images and optical thumbnails) are available in the Milan XMM-LSS database site.
- ID:
- ivo://CDS.VizieR/J/MNRAS/429/1652
- Title:
- XMM-LSS catalogue. Version II.
- Short Name:
- J/MNRAS/429/1652
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the final release of the multiwavelength XMM-Large Scale Structure (LSS) data set, covering the full survey area of 11.1deg^2^, with X-ray data processed with the latest XMM-LSS pipeline version. The present publication supersedes the catalogue from the first paper in this series, pertaining to the initial 5deg^2^. We provide X-ray source lists in the customary energy bands (0.5-2 and 2-10keV) for a total of 6721 objects in the deep full-exposure catalogue and 5572 in the catalogue limited to 10ks, above a detection likelihood of 15 in at least one band. We also provide a multiwavelength catalogue, cross-correlating our list with infrared, near-infrared, optical and ultraviolet catalogues. Customary data products, such as X-ray fits images and thumbnail images from the Canada-France-Hawaii Telescope Legacy Survey and the Spitzer Wide-Area Infrared Extragalactic Survey, are made available, together with our data base in Milan, which can be queried interactively.
- ID:
- ivo://CDS.VizieR/J/A+A/456/791
- Title:
- XMM-LSS field at 74 and 325MHz
- Short Name:
- J/A+A/456/791
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The XMM Large Scale Structure survey (XMM-LSS) is an X-ray survey aimed at studying the large scale structure of the Universe. The XMM-LSS field is currently being followed up using observations across a wide range of wavelengths, and in this paper we present the observational results of a low frequency radio survey of the XMM-LSS field using the Very Large Array at 74 and 325MHz. This survey will map out the locations of the extragalactic radio sources relative to the large scale structure as traced by the X-ray emission. This is of particular interest because radio galaxies and radio loud AGN show strong and complex interactions with their small and larger scale environment, and different classes of radio galaxies are suggested to lie at different places with respect to the large scale structure.