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Mid-infrared sources in the ELAIS Deep X-ray Survey

J. C. Manners·S. Serjeant·S. Bottinelli·M. Vaccari·A. Franceschini·I. Perez-Fournon·E. Gonzalez-Solares·C. J. Willott·O. Johnson·O. Almaini·M. Rowan-Robinson·S. Oliver
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Abstract

We present a cross-correlation of the European Large Area ISO survey (ELAIS) with the ELAIS Deep X-ray Survey of the N1 and N2 fields. There are 7 Chandra point sources with matches in the ELAIS Final Analysis 15um catalogue, out of a total of 28 extragalactic ISO sources present in the Chandra fields. Five of these are consistent with AGN giving an AGN fraction of ~19 per cent in the 15um flux range 0.8-6 mJy. We have co-added the hard X-ray fluxes of the individually-undetected ISO sources and find a low significance detection consistent with star formation in the remaining population. We combine our point source cross-correlation fraction with the XMM-Newton observations of the Lockman Hole and Chandra observations of the Hubble Deep Field North to constrain source count models of the mid-infrared galaxy population. The low dust-enshrouded AGN fraction in ELAIS implied by the number of cross-identifications between the ELAIS mid-infrared sample and the Chandra point sources is encouraging for the use of mid-infrared surveys to constrain the cosmic star formation history, provided there are not further large undetected populations of Compton-thick AGN.

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J. C. Manners, S. Serjeant, S. Bottinelli, M. Vaccari, A. Franceschini, I. Perez-Fournon, E. Gonzalez-Solares, C. J. Willott, O. Johnson, O. Almaini, M. Rowan-Robinson, S. Oliver. 2004-09-29. Mid-infrared sources in the ELAIS Deep X-ray Survey. https://doi.org/10.1111/j.1365-2966.2004.08293.x

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