XMM-COSMOS Catalog of Optical/IR Counterparts

XMM-COSMOS Catalog of Optical/IR Counterparts XMMCOSMOID ivo://nasa.heasarc/xmmcosmoid NASA/GSFC HEASARC Brusa et al. 2026-06-26 NASA/GSFC HEASARC help desk heasarc-vo at athena.gsfc.nasa.gov Survey Source This table contains the final optical identifications of the medium-depth (~60 ks), contiguous (2 degree2) XMM-Newton survey of the COSMOS field. XMM-Newton has detected ~1800 X-ray sources down to limiting fluxes of ~5 x 10-16, ~3 x 10-15, and ~7 x 10-15 erg cm-2 s-1 in the 0.5-2 keV, 2-10 keV, and 5-10 keV bands, respectively (~1 x 10-15, ~6 x 10-15, and ~1 x 10-14 erg cm-2 s-1, in the three bands, respectively, over 50% of the area). The work is complemented by an extensive collection of multi-wavelength data from 24 microns to UV, available from the COSMOS survey, for each of the X-ray sources, including spectroscopic redshifts for >~50% of the sample, and high-quality photometric redshifts for the rest. The XMM-Newton and multi-wavelength flux limits are well matched: 1760 (98%) of the X-ray sources have optical counterparts, 1711 (~95%) have IRAC counterparts, and 1394 (~78%) have MIPS 24 um detections. Thanks to the redshift completeness (almost 100%) the authors were able to constrain the high-luminosity tail of the X-ray luminosity function confirming that the peak of the number density of log LX > 44.5 active galactic nuclei (AGNs) is at z ~ 2. Spectroscopically identified obscured and unobscured AGNs, as well as normal and star-forming galaxies, present well-defined optical and infrared properties. The authors devised a robust method to identify a sample of ~150 high-redshift (z > 1), obscured AGN candidates for which optical spectroscopy is not available. They were able to determine that the fraction of the obscured AGN population at the highest (LX > 1044 erg s-1) X-ray luminosity is ~15%-30% when selection effects are taken into account, providing an important observational constraint for X-ray background synthesis. The authors studied in detail the optical spectrum and the overall spectral energy distribution of a prototypical Type 2 QSO (source number 2028), caught in a stage transitioning from being starburst dominated to AGN dominated, which was possible to isolate only thanks to the combination of X-ray and infrared observations. This table was created by the HEASARC in July 2010 based on the electronic version of Table 2 from the paper which was obtained from the Astrophysical Journal web site. The HEASARC has made some changes to this material in order to make it more compliant with CDS/IAU Nomenclature and HEASARC table standards: (i) The original naming convention suggested by the authors used a prefix of 'XMMC_' and the J2000.0 RA and Dec position in decimal degrees to 10-5 degrees precision, e.g., XMMC_150.10515+1.98082'; the HEASARC has replaced these names by alternative new ones (in the alt_name parameter) of the form 'XMMU JHHMMSS.s+DDMMSS' where the prefix is the usual one for XMM-Newton sources and the remainder of the field is the J2000.0 equatorial coordinates truncated to 0.1 seconds of time in RA and to 1 arcsecond in Declination; (ii) We have used for the alt_name parameter the naming convention recommended by the Dictionary of Nomenclature of Celestial Objects for XMM-COSMOS sources, viz. the "XMMC' prefix and the source (XID) number, e.g., "XMMC 2028'. This is a service provided by NASA HEASARC . 2010ApJ...716..348B https://heasarc.gsfc.nasa.gov/W3Browse/all/xmmcosmoid.html Catalog Research served-by HEASARC TAP https://heasarc.gsfc.nasa.gov/xamin/vo/cone?showoffsets&table=xmmcosmoid& GET text/xml 180 99999 true 150.3554535 1.4723361 0.0166666666666667 https://heasarc.gsfc.nasa.gov/xamin/vo/tap https://heasarc.gsfc.nasa.gov/cgi-bin/W3Browse/getvotable.pl?name=xmmcosmoid GET text/xml https://heasarc.gsfc.nasa.gov/cgi-bin/W3Browse/w3query.pl?tablehead=name=heasarc_xmmcosmoid&Action=More+Options&Action=Parameter+Search&ConeAdd=1 XMM-NEWTON 0.0166666666666667 Infrared Optical public xmmcosmoid XMM-COSMOS Catalog of Optical/IR Counterparts name Source Designation meta.id;meta.main char nullable ra Right Ascension degree pos.eq.ra;meta.main double nullable dec Declination degree pos.eq.dec;meta.main double nullable sb_flux 0.5-2 keV Flux from Cappelluti et al. 2009 (erg/s/cm^2) erg/s/cm^2 phot.flux;em.X-ray.soft double nullable hb_flux 2-10 keV Flux from Cappelluti et al. 2009 (erg/s/cm^2) erg/s/cm^2 phot.flux;em.X-ray.medium double nullable rmag Capak et al. 2007 r-Band AB Magnitude mag phot.mag;em.opt.R double nullable flux_3p6_um Ilbert et al. 2009 IRAC 3.6 micron Band AB Flux microJy phot.flux.density;em.IR.3-4um double nullable redshift Spectroscopic Redshift src.redshift double nullable phot_redshift Salvato et al. 2009 Photometric Redshift src.redshift double nullable class Browse Object Classification src.class short nullable imag Capak et al. 2007 I-Band AB Magnitude mag phot.mag;em.opt.I double nullable fls_flag Flag Indicates Source in Flux-Limited Sample meta.code short nullable ref_redshift Reference for Redshift meta.ref;src.redshift short nullable capak_source_number Capak et al. 2007 Catalog Identifier Number meta.id.cross int nullable source_number Sequential Identification Number for Each Source in Catalog meta.id;src int nullable ilbert_source_number Ilbert et al. 2009 Catalog Identifier Number meta.id.cross int nullable hardness_ratio Hardness Ratio phot.flux;arith.ratio;em.X-ray double nullable broad_type Broad Classification of Source src.class short nullable alt_name Alternative Catalog-Based Source Designation meta.id char nullable optical_ident_flag Flag Indicates Optical Identification meta.code short nullable bii Galactic Latitude degree pos.galactic.lat double nullable lii Galactic Longitude degree pos.galactic.lon double nullable flux_4p5_um Ilbert et al. 2009 IRAC 4.5 micron Band AB Flux microJy phot.flux.density;em.IR.4-8um double nullable uhb_flux 5-10 keV Flux from Cappelluti et al. 2009 (erg/s/cm^2) erg/s/cm^2 phot.flux;em.X-ray.medium double nullable flux_8p0_um Ilbert et al. 2009 IRAC 8.0 micron Band AB Flux microJy phot.flux.density;em.IR.4-8um double nullable flux_24_um Le Floch et al. 2009 MIPS 24 micron Band AB Flux mJy phot.flux.density;em.IR.15-30um double nullable kmag McCraken et al. 2009 K-Band AB Magnitude mag phot.mag;em.IR.K double nullable ccosmos_source_number Elvis et al. 2009 Chandra-COSMOS Identifier Number meta.id.cross int nullable flux_5p8_um Ilbert et al. 2009 IRAC 5.8 micron Band AB Flux microJy phot.flux.density;em.IR.4-8um double nullable "__x_ra_dec" System unit vector column double nullable "__y_ra_dec" System unit vector column double nullable "__z_ra_dec" System unit vector column double nullable "__row" System index column char nullable