J/MNRAS/371/1891 GOODS ELAIS-N1 24um flux densities (Rodighiero+, 2006)
Counting individual galaxies from deep 24-µm Spitzer surveys.
Rodighiero G., Lari C., Pozzi F., Gruppioni C., Fadda D., Franceschini A.,
Lonsdale C., Surace J., Shupe D., Fang F.
<Mon. Not. R. Astron. Soc., 371, 1891-1897 (2006)>
=2006MNRAS.371.1891R 2006MNRAS.371.1891R
ADC_Keywords: Surveys ; Infrared sources
Keywords: methods: data analysis - catalogues - galaxies: photometry -
infrared: galaxies - infrared: general
Abstract:
We address the question of how to deal with confusion-limited
surveys in the mid-infrared (MIR) domain by using information from
shorter-wavelength observations over the same sky regions. Such
information, once applied to apparently extended MIR sources, which
are indeed 'blends' of two or more different sources, allow us to
disentangle the single counterparts and to split the measured flux
density into different components. We present the application of
this method to the 24-µm Spitzer archival data in the Great
Observatories Origins Deep Survey ELAIS-N1 (GOODS EN1) test field,
where apparently extended, 'blended' sources constitute about 20 per
cent of a reliable sample of 983 sources detected above the 5σ
threshold down to 40uJy. As a shorter-wavelength data set, we have
considered the public Infrared Array Camera (IRAC) images and
catalogues of the same field. We show that the 24-µm sample is
almost unbiased down to ∼40uJy and the careful application of the
deblending procedure does not require any statistical completeness
correction (at least at the flux level considered). This is probed by
direct comparison of our results with results in the literature that
analysed the same data set through extensive Monte Carlo simulations.
The extrapolation of the source counts down to fainter fluxes suggests
that our 24-µm sample is able to resolve ∼62 per cent of the cosmic
background down to a flux level of 38uJy.
Description:
The EN1 field is one of the best areas, among those currently
available, for investigating the effects of source confusion in MIR
surveys. Deep MIPS 24-µm observations in this field cover an area
of ∼185arcmin2 (centred at RA=16:09:20, DE=+54:57:00) as part of the
GOODS Science Verification programme of Spitzer. The field was
observed in photometry mode.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 62 983 GOODS EN1 validation field - 24 micron catalogue
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See also:
II/255 : SWIRE ELAIS N1 Source Catalogs (Surace+, 2004)
J/AJ/129/1198 : SDSS quasars in SWIRE ELAIS N1 field (Hatziminaoglou+, 2005)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 17 A17 --- [RLP2006] Source designation (EN1-HHMMSS+DDMMSS)
21- 22 I2 h RAh Right ascension (J2000)
24- 25 I2 min RAm Right ascension (J2000)
27- 32 F6.3 s RAs Right ascension (J2000)
35 A1 --- DE- Declination sign (J2000)
36- 37 I2 deg DEd Declination (J2000)
39- 40 I2 arcmin DEm Declination (J2000)
42- 47 F6.3 arcsec DEs Declination (J2000)
52- 54 I3 --- S/N Signal-to-noise ratio
58- 61 I4 uJy S24um Total flux density at 24um
62 A1 --- n_S24um [*] *: source classified as star
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 29-May-2007