XWAS - XMM-Newton Wide Angle Survey

Overview

This table contains results from the XMM-Newton Wide Angle Survey (XWAS), viz., a new catalog of almost a thousand X-ray sources that have been spectroscopically identified through optical observations. The sources lie in high-galactic latitude (|b| > 20 degrees) XMM-Newton fields mainly in the southern hemisphere.

A sample of X-ray sources detected in 68 XMM-Newton pointed observations was selected for optical multi-fiber spectroscopy. Optical counterparts and corresponding photometry of the X-ray sources were obtained from the SuperCOSMOS Sky Survey. Candidates for spectroscopy were initially selected with magnitudes down to R ~ 21, with preference for X-ray sources having a flux F_0.5-4.5keV >= 10^-14 erg/s/cm². Optical spectroscopic observations were made using the Two Degree Field of the Anglo-Australian Telescope, and the resulting spectra were classified based on optical emission lines. The authors have identified through optical spectroscopy 940 X-ray sources over a solid angle Omega ~ 11.8 deg² of the sky. Source populations in their sample can be summarized as 65% broad-line active galactic nuclei (BLAGN), 16% narrow emission-line galaxies (NELGs), 6% absorption-line galaxies (ALGs) and 13% stars. An active nucleus is also likely to be present in the large majority of the X-ray sources spectroscopically classified as NELGs or ALGs.

Optical images are available for all of the XWAS fields in the SuperCOSMOS Sky Survey (Hambly et al., 2001, MNRAS, 326, 1279).

Catalog Bibcode

2013A&A...557A.123E

References

The XMM-Newton Wide Angle Survey (XWAS).
    Esquej P., Page M., Carrera F.J., Mateos S., Tedds J., Watson M.G.,
    Corral A., Ebrero J., Krumpe M., Rosen S.R., Ceballos M.T., Schwope A.,
    Page C.G., Alonso-Herrero A., Caccianiga A., Della Ceca R.,
    Gonzalez-Martin O., Lamer G., Severgnini P.
   <Astron. Astrophys., 557, A123 (2013)>
   =2013A&A...557A.123E    (SIMBAD/NED BibCode)

Provenance

This table was created by the HEASARC in May 2017 based upon the CDS Catalog J/A+A/557/A123 file xwas_cat.dat.

Parameters

Name
The J2000.0 position-based XWAS source designation, viz., 'XWAS JHHMMSS.s+DDMMSS'. This naming convention has not been registered with the Dictionary of Nomenclature of Celestial Objects, so these names are not currently recognized by Simbad and the prefix of '2XMM' should replace the 'XWAS' prefix when doing Simbad searches by name.

Optical_ID
An identifier for the optical counterpart to the XMM-Newton X-ray source, viz., 'XNNNNN_NNN' or 'XLSS_NNNNN'. This identifier (referred to as OPTID in the reference paper) is derived from the 2dF observations.

RA
The Right Ascension of the 2dF fiber position of the optical counterpart to the XMM-Newton X-ray source in the selected equinox, i.e., not the Right Ascension of the X-ray source in the XMM-Newton Serendipitous Survey (Watson et al., 2001, A&A, 365, L51). This was given in J2000.0 equatorial coordinates to a precision of 0.01 seconds of time in the original table.

Dec
The Declination of the 2dF fiber position of the optical counterpart to the XMM-Newton X-ray source in the selected equinox, i.e., not the Declination of the X-ray source in the XMM-Newton Serendipitous Survey (Watson et al., 2001, A&A, 365, L51). This was given in J2000.0 equatorial coordinates to a precision of 0.1 arcseconds in the original table.

LII
The Galactic Longitude of the 2dF fiber position of the optical counterpart to the XMM-Newton X-ray source.

BII
The Galactic Latitude of the 2dF fiber position of the optical counterpart to the XMM-Newton X-ray source.

Redshift
The redshift of the optical counterpart to the XMM-Newton X-ray source as derived from the authors' analysis of the 2dF observations.

Broad_Type
The source classification of the optical counterpart to the XMM-Newton X-ray source as derived from the authors' analysis of the 2dF observations.

Flux
The absorbed flux of the XMM-Newton source in the (0.5-4.5) keV energy band taken from the XMM-Newton Serendipitous Survey (Watson et al., 2001, A&A, 365, L51), in erg s^-1 cm^-2.

Log_Lx
The logarithm of the absorbed X-ray luminosity of the XMM-Newton source in the (0.5-4.5) keV (rest-frame) band, in erg s^-1, calculated using the absorbed flux and the derived redshift. This is not given for those X-ray sources that have been identified as (Galactic) stars.

Supercosmos_ID
The object identifier (OBJID) of the SuperCOSMOS counterpart to the XMM-Newton X-ray source.

Rmag
The R magnitude (Vega) of the SuperCOSMOS counterpart to the XMM-Newton X-ray source. Where possible, the authors have used the R2 magnitude, else they quote the R1 magnitude.

Bmag
The B magnitude (Vega) of the SuperCOSMOS counterpart to the XMM-Newton X-ray source.

Class
The HEASARC Browse object classification, based on the value of the broad_type parameter.

Contact Person

Questions regarding the XWAS database table can be addressed to the HEASARC Help Desk.

Page Author: Browse Software Development Team
Last Modified: Monday, 16-Sep-2024 17:37:44 EDT