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The European Large Area ISO Survey: optical identifications of 15-mum and 1.4-GHz sources in N1 and N2

Gonzalez-Solares, E.A.; Perez-Fournon, I.; Rowan-Robinson, M.; Oliver, S.; Vaccari, M.; Lari, C.; Irwin, M.; McMahon, R.G.; Hodgkin, S.; Ciliegi, P.; Serjeant, S. and Willott, C.J. (2005). The European Large Area ISO Survey: optical identifications of 15-mum and 1.4-GHz sources in N1 and N2. Monthly Notices of the Royal Astronomical Society, 358(2) pp. 333–340.

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We present the multiwavelength properties and catalogue of the 15mum and 1.4GHz radio sources detected in the European Large Area ISO Survey (ELAIS) areas N1 and N2. Using the optical data from the Wide Field Survey we use a likelihood ratio method to search for the counterparts of the 1056 and 691 sources detected at 15mum and 1.4GHz, respectively, down to flux limits of S15= 0.5mJy and S1.4GHz= 0.135mJy. We find that ~92 per cent of the 15mum ELAIS sources have an optical counterpart down to r'= 24. All mid-infrared (IR) sources with fluxes S15>= 3mJy have an optical counterpart. The magnitude distribution of the sources shows a well-defined peak at relatively bright magnitudes r'~ 18. The mid-IR-to-optical and radio-to-optical flux diagrams are presented and discussed in terms of actual galaxy models. About 15 per cent of the sources are bright galactic stars; of the extragalactic objects ~65 per cent are compatible with being normal or starburst galaxies and ~25 per cent active galactic nuclei (AGNs). Objects with mid-IR-to-optical fluxes larger than 100 are found, comprising ~20 per cent of the sample. We suggest that that these sources are highly obscured luminous and ultraluminous starburst galaxies and AGNs.

Item Type: Article
ISSN: 1365-2966
Extra Information: Some of the symbols may not have transferred correctly into this bibliographic record and/or abstract.
Academic Unit/School: Faculty of Science, Technology, Engineering and Mathematics (STEM) > Physical Sciences
Faculty of Science, Technology, Engineering and Mathematics (STEM)
Interdisciplinary Research Centre: Centre for Earth, Planetary, Space and Astronomical Research (CEPSAR)
Item ID: 5646
Depositing User: Users 13 not found.
Date Deposited: 25 Oct 2006
Last Modified: 04 Oct 2016 09:55
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