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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.
| The Nature of the Mid-Infrared Population from Optical Identifications of the ELAIS-S1 Sample
We present a multiwavelength catalog (15 μm, R-band, K-band, and 1.4GHz flux) plus spectroscopic identifications for 406 15 μm sourcesdetected in the European Large Area ISO Survey (ELAIS) region S1, overthe flux density range 0.5
| A new method for ISOCAM data reduction - I. Application to the European Large Area ISO Survey Southern Field: method and results
We develop a new data reduction technique for ISOCAM LW data and applyit to the European Large Area ISO Survey (ELAIS) LW3 (15-μm)observations in the southern hemisphere (S1). This method, known as LARItechnique and based on the assumption of the existence of two differenttime-scales in ISOCAM transients (accounting for either fast or slowdetector response), is particularly designed for the detection of faintsources. In the ELAIS S1 field we obtain a catalogue of 462 15-μmsources with signal-to-noise ratios >=5 and flux densities in therange 0.45-150mJy (filling the whole flux range between the Deep ISOCAMSurveys and the IRAS Faint Source Survey). The completeness at differentflux levels and the photometric accuracy of this catalogue are testedwith simulations. Here we present a detailed description of the methodand discuss the results obtained by its application to the S1 LW3 data.
| A large, complete, volume-limited sample of G-type dwarfs. I. Completion of Stroemgren UVBY photometry
Four-colour photometry of potential dwarf stars of types G0 to K2,selected from the Michigan Spectral Catalogues (Vol. 1-3), has beencarried out. The results are presented in a catalogue containing 4247uvby observations of 3900 stars, all south of δ = -26deg. Theoverall internal rms errors of one observation (transformed to thestandard system) of a program star in the interval 8.5 < V < 10.5are 0.0044, 0.0021, 0.0039, and 0.0059, respectively, in V, b-y, m_1_ ,and c_1_. The purpose of the catalogue, combined with earliercatalogues, is to allow selection of a large, complete, volume-limitedsample of G- and K-type dwarfs, investigate their metallicitydistribution, and compare it to predictions of various models ofgalactic chemical evolution. Future papers in this series will discussthese subjects.
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| Сазвежђа: | Феникс |
| Ректацензија: | 00h32m30.65s |
| Deклинација: | -44°03'57.5" |
| Apparent магнитуда: | 8.875 |
| Даљина: | 169.492 parsecs |
| Proper motion RA: | 15.7 |
| Proper motion Dec: | 3.3 |
| B-T magnitude: | 10.025 |
| V-T magnitude: | 8.97 |
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