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The European Large-Area ISO Survey (ELAIS): the final band-merged catalogue We present the final band-merged European Large-Area ISO Survey (ELAIS)Catalogue at 6.7, 15, 90 and 175 μm, and the associated data at U,g', r', i', Z, J, H, K and 20 cm. The origin of the survey, infrared andradio observations, data-reduction and optical identifications arebriefly reviewed, and a summary of the area covered and the completenesslimit for each infrared band is given. A detailed discussion of theband-merging and optical association strategy is given. The totalCatalogue consists of 3762 sources. 23 per cent of the 15-μm sourcesand 75 per cent of the 6.7-μm sources are stars. For extragalacticsources observed in three or more infrared bands, colour-colour diagramsare presented and discussed in terms of the contributing infraredpopulations. Spectral energy distributions (SEDs) are shown for selectedsources and compared with cirrus, M82 and Arp220 starburst, and activegalactic nuclei (AGN) dust torus models.Spectroscopic redshifts are tabulated, where available. For the N1 andN2 areas, the Isaac Newton Telescope ugriz Wide Field Survey permitsphotometric redshifts to be estimated for galaxies and quasars. Theseagree well with the spectroscopic redshifts, within the uncertainty ofthe photometric method [~10 per cent in (1 +z) for galaxies]. Theredshift distribution is given for selected ELAIS bands andcolour-redshift diagrams are discussed.There is a high proportion of ultraluminous infrared galaxies(log10 of 1-1000 μm luminosity Lir > 12.22)in the ELAIS Catalogue (14 per cent of 15-μm galaxies with known z),many with Arp220-like SEDs. 10 per cent of the 15-μm sources aregenuine optically blank fields to r'= 24: these must have very highinfrared-to-optical ratios and probably have z > 0.6, so arehigh-luminosity dusty starbursts or Type 2 AGN. Nine hyperluminousinfrared galaxies (Lir > 13.22) and nine extremely redobjects (EROs) (r-K > 6) are found in the survey. The latter areinterpreted as ultraluminous dusty infrared galaxies at z~ 1. The largenumbers of ultraluminous galaxies imply very strong evolution in thestar formation rate between z= 0 and 1. There is also a surprisinglylarge population of luminous (Lir > 11.5), cool(cirrus-type SEDs) galaxies, with Lir-Lopt > 0,implying AV > 1.
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Takýmyýldýz: | Coban |
Sað Açýklýk: | 14h24m48.52s |
Yükselim: | +33°05'27.8" |
Görünürdeki Parlaklýk: | 9.676 |
özdevim Sað Açýklýk: | 4.3 |
özdevim Yükselim: | -7.6 |
B-T magnitude: | 10.474 |
V-T magnitude: | 9.742 |
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