Open AccessMid‐infrared sources in the ELAIS Deep X‐ray Survey
Author(s) -
Manners J. C.,
Serjeant S.,
Bottinelli S.,
Vaccari M.,
Franceschini A.,
PerezFour I.,
GonzalezSolares E.,
Willott C. J.,
Johnson O.,
Almaini O.,
RowanRobinson M.,
Oliver S.
Publication year - 2004
Publication title -
monthly notices of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.058
H-Index - 383
eISSN - 1365-2966
pISSN - 0035-8711
DOI - 10.1111/j.1365-2966.2004.08293.x
Subject(s) - physics , astrophysics , galaxy , active galactic nucleus , cosmic infrared background , infrared , source counts , astronomy , hubble deep field , star formation , flux (metallurgy) , population , chandra deep field south , point source , luminous infrared galaxy , hubble space telescope , redshift , cosmic microwave background , demography , anisotropy , quantum mechanics , metallurgy , materials science , sociology , optics
We present a cross‐correlation of the European Large Area Infrared Space Observatory ( ISO ) survey (ELAIS) with the ELAIS Deep X‐ray Survey of the N1 and N2 fields. There are seven Chandra point sources with matches in the ELAIS Final Analysis 15‐μm catalogue, out of a total of 28 extragalactic ISO sources present in the Chandra fields. Five of these are consistent with active galactic nuclei (AGN) giving an AGN fraction of ∼19 per cent in the 15‐μm 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.