J/ApJ/714/1305 The Deep SWIRE Field (DSF) IV. (Strazzullo+, 2010)
The Deep SWIRE Field.
IV. First properties of the sub-mJy galaxy population:
redshift distribution, AGN activity, and star formation.
Strazzullo V., Pannella M., Owen F.N., Bender R., Morrison G.E.,
Wang W.-H., Shupe D.L.
<Astrophys. J., 714, 1305-1323 (2010)>
=2010ApJ...714.1305S 2010ApJ...714.1305S
ADC_Keywords: Active gal. nuclei ; Galaxies, IR ; Galaxies, radio ;
Magnitudes, absolute ; Redshifts
Keywords: cosmology: observations - galaxies: active - galaxies: evolution -
galaxies: starburst - radio continuum: galaxies
Abstract:
We present a study of a 20cm selected sample in the Deep Spitzer
Wide-area InfraRed Extragalactic Legacy Survey Very Large Array Field,
reaching a 5σ limiting flux density at the image center of
S1.4GHz∼13.5uJy. In a 0.6x0.6deg2 field, we are able to assign an
optical/IR counterpart to 97% of the radio sources. Up to 11 passbands
from the NUV to 4.5um are then used to sample the spectral energy
distribution (SED) of these counterparts in order to investigate the
nature of the host galaxies. By means of an SED template library and
stellar population synthesis models, we estimate photometric
redshifts, stellar masses, and stellar population properties, dividing
the sample into three sub-classes of quiescent, intermediate, and
star-forming galaxies. We focus on the radio sample in the redshift
range 0.3<z<1.3 where we estimate to have a redshift completeness
higher than 90% and study the properties and redshift evolution of
these sub-populations.
Description:
The sample of radio sources used here is described in detail in paperI
(Owen & Morrison 2008, Cat. J/AJ/136/1889). The Deep SWIRE Field (DSF)
was observed with the VLA in the A, B, C, and D configurations for a
total of almost 140hr on-source between 2001 December and 2004
January. The final image has a resolution of 1.6", with a typical rms
at the center of the image of 2.7uJy (see paper I for details).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 64 1580 Main derived properties used in this work
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See also:
J/ApJS/182/625 : WIYN spectroscopy in the deep SWIRE field (Owen+, 2009)
J/AJ/137/4846 : 90cm observations of the deep SWIRE field (Owen+, 2009)
J/AJ/136/1889 : 20cm observations of deep Swire Field (Owen+, 2008)
J/AJ/105/853 : Energy distributions of radio galaxies (Impey+ 1993)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 5 I5 --- [OM2008] Identification number (1)
7- 8 I2 h RAh Hour of Right Ascension (J2000) (1)
10- 11 I2 min RAm Minute of Right Ascension (J2000) (1)
13- 17 F5.2 s RAs Second of Right Ascension (J2000) (1)
19 A1 --- DE- Sign of declination (J2000) (1)
20- 21 I2 deg DEd Degree of Declination (J2000) (1)
23- 24 I2 arcmin DEm Arcminute of Declination (J2000) (1)
26- 29 F4.1 arcsec DEs Arcsecond of Declination (J2000) (1)
31- 34 F4.2 --- z Redshift, spectroscopic if e_z is blank (2)
36- 39 F4.2 --- e_z ? Uncertainty in z
41- 42 A2 --- q_z Quality flag in z (3)
44- 48 F5.1 mag RMag ? Synthetic Johnson R band absolute AB mag. (4)
50- 53 F4.2 mag U-B ? Synthetic restframe (U-B) AB color index (4)
55- 59 F5.2 [Msun] logM ? Log base 10 of stellar mass; Salpeter IMF (4)
61- 64 F4.2 [Msun] e_logM ? Uncertainty in logM
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Note (1): As in Paper I (Owen & Morrison 2008, Cat. J/AJ/136/1889). Note that
only objects with available spectroscopic redshift or reliable photo-z
are listed. See text for details about how these quantities were
derived.
Note (2): Spectroscopic redshift where available, otherwise photometric
redshift. Redshifts without an error listed are spectroscopic.
Note (3): Quality flag for photometric redshifts, as defined in section 5.1 as
follows:
AA = a photo-z is determined in all different realizations, the total number
of upper limits plus flagged magnitudes is less than 5, the maximum
difference Δz/(1+z) among the different determinations is less
than 20%, the estimated error on the photo-z is less than 0.2(1+z).
A = same as AA but the constrain on the estimated error is relaxed to
0.4(1+z).
B = same as A but constrain on the number of flagged magnitudes plus upper
limits is increased to less than 7.
C1 = same as B but no constrain on the estimated error on photo-z.
Note (4): Assuming the redshift listed in column 4. Both R band magnitude
and stellar mass estimates are based on SED fitting in a 1.5" aperture
and corrected for each object based on the difference between total
and aperture magnitudes as measured in the detection image, as
explained in section 6.
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History:
From electronic version of the journal
References:
Owen & Morrison., Paper I. 2008AJ....136.1889O 2008AJ....136.1889O, Cat. J/AJ/136/1889
Owen F.N. et al., Paper II. 2009AJ....137.4846O 2009AJ....137.4846O, Cat. J/AJ/137/4846
Owen F.N. et al., Paper III. 2009ApJS..182..625O 2009ApJS..182..625O, Cat. J/ApJS/182/625
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 23-Apr-2012