Abstract
Since its launch in 1999, the XMM-Newton mission has compiled the largest catalogue of serendipitous X-ray sources, with the 3XMM being the third version of this catalogue. This was possible thanks to the combination of a large effective area (5000 cm2 at 1 keV) and a wide field of view (30 arcmin). The 3XMM-DR6 catalogue contains about 470 000 unique X-ray sources over an area of 982 deg2. A significant fraction of these (100 178 sources) have reliable optical, near-(NIR), and mid-infrared (MIR) counterparts in the SDSS, PANSTARRS, VIDEO, UKIDSS, and WISE surveys. In a previous paper we presented photometric redshifts for these sources using the TPZ machine-learning algorithm. About a quarter of these (22 677) have adequate photon statistics, meaning that a reliable X-ray spectrum can be extracted. Owing to both the X-ray counts selection and the optical counterpart constraint, the sample above is biased towards the bright sources. Here, we present XMMFITCAT-Z: a spectral fit catalogue for these sources using the Bayesian X-ray Analysis technique. To demonstrate the potential of the present catalogue, we comment on the optical and MIR colours of the 765 X-ray absorbed sources with NH > 1022 cm−2. We show that a considerable fraction of X-ray-selected AGNs would not be classified as AGNs following the MIR W1–W2 versus W2 selection criterion. These are AGNs with lower luminosities, where the contribution of the host galaxy to the MIR emission is non-negligible. Only one-third of obscured AGNs in X-rays present red colours or r–W2 > 6. Also, it appears that the r–W2 criterion, often used in the literature for the selection of obscured AGNs, produces very different X-ray absorbed AGN samples compared to the standard X-ray selection criteria.
Highlights
The XMM-Newton mission (Jansen et al 2001) launched in 1999 is the second cornerstone mission of the European Space Agency (ESA)
We present a catalogue of automated X-ray spectral fits using the 3XMM-DR6 spectral products
We present 22 677 X-ray sources with an X-ray spectrum of reasonable quality, meaning that each XMM-Newton detector has over 50 counts, and for which a photometric or spectroscopic redshift is
Summary
The XMM-Newton mission (Jansen et al 2001) launched in 1999 is the second cornerstone mission of the European Space Agency (ESA). It carries three telescopes with the largest effective area in an X-ray telescope so far (combined 5000 cm at 1 keV). These telescopes focus the light on the European Photon Imaging Camera (EPIC) CCD cameras. The 3XMM covers about 1000 square degrees and contains about half a million unique sources. This is the largest catalogue of X-ray sources ever produced. The median flux of the sources is ∼2.4 × 10−14 erg cm−2 s−1 in the total 0.2–12 keV band
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