XMM-Newton Large-Scale Structure Optical Identifications Catalog

This table contains optical spectroscopic identifications of X-ray sources in ~3 square degrees of the XMM-Large Scale Structure survey (XMM-LSS), also covered by the Canada-France-Hawaii Telescope Legacy Survey (CFHTLS), which were obtained with the AAOmega instrument at the 3.9-m Anglo-Australian Telescope during the nights of 2006 September 25-27 and 2007 September 11-13. In a flux-limited sample of 829 point-like sources in the optical band with g' <= 22 magnitudes and the 0.5-2 keV flux (f_0.5-2keV) > 10<sup>-15</sup> erg/cm<sup>2</sup>/s, the authors observed 693 objects and obtained reliable spectroscopic identification for 487 sources, approximately 59% of the overall sample. The authors therefore have increased the number of identifications in this field by a factor close to 5. Galactic stellar sources represent about 15% of the total (74/487). About 54% (265/487) are broad-line active galactic nuclei (AGN) spanning redshifts between 0.15 and 3.87 with a median value of 1.68. The optical-to-X-ray spectral index (alpha_ox) of the broad-line AGN is 1.47 +/- 0.03, typical of optically selected type I quasars, and is found to correlate with the rest-frame X-ray and optical monochromatic luminosities at 2 keV and 2500 Angstroms, respectively. Consistent with previous studies, the authors find that alpha_ox is not correlated with z. In addition, 32 and 116 X-ray sources are, respectively, absorption- and emission-line galaxies at z < 0.76. From a line ratio diagnostic diagram, it is found that in about 50% of these emission-line galaxies, the emission lines are powered significantly by the AGN. 30 of the XMM sources are detected at one or more radio frequencies (see Table 5 in the published paper). In addition, 24 sources (listed in table 4 of the published paper) have ambiguous identification: in eight cases, two XMM sources have a single optical source within 6 arcsec of each of them, whereas two and 14 XMM sources have, respectively, three and two possible optical sources within 6 arcsec of each of them. Spectra of multiple possible counterparts were obtained in such ambiguous cases. This HEASARC table contains the 487 sources which were reliably spectroscopically identified.

Source https://heasarc.gsfc.nasa.gov/W3Browse/all/xmmlssoid.html
Metadata Access http://dc.g-vo.org/rr/q/pmh/pubreg.xml?verb=GetRecord&metadataPrefix=oai_datacite&identifier=ivo://nasa.heasarc/xmmlssoid
Creator Stalin et al.
Publication Year 2020
Contact Michael Preciado <Michael.E.Preciado@nasa.gov>
Resource Type AstroObjects
Format text/xml
Discipline Various