The XMM-Newton survey in the H-ATLAS field

Wide-area X-ray and far-infrared surveys are a fundamental tool to investigate the link between AGN growth and star formation, especially in the low-redshift universe (z ≲ 1). The Herschel Terahertz Large Area survey (H-ATLAS) has covered 550 deg2 in five far-infrared and sub-mm bands, 16 deg2 of which have been presented in the Science Demonstration Phase (SDP) catalogue. Here we introduce the XMM-Newton observations in the H-ATLAS SDP area, covering 7.1 deg2 with flux limits of 2 × 10-15, 6 × 10-15, and 9 × 10-15 erg s-1 cm-2 in the 0.5−2, 0.5−8, and 2−8 keV bands, respectively. We present the source detection and the catalogue, which includes 1700, 1582, and 814 sources detected by EMLDetect in the 0.5−8, 0.5−2, and 2−8 keV bands, respectively; the number of unique sources is 1816. We extract spectra and derive fluxes from power-law fits for 398 sources with more than 40 counts in the 0.5−8 keV band. We compare the best-fit fluxes with those in the catalogue, which are obtained assuming a common photon index of Γ = 1.7; we find no bulk difference between the fluxes and a moderate dispersion of s = 0.33 dex. Using the fluxes from the spectral fits wherever possible, we derive the 2−10 keV Log N−Log S, which is consistent with a Euclidean distribution. Finally, we release the computer code for the tools developed for this project.