J/AJ/131/1216 Faint radio sources in the CDF-S ACS field (Afonso+, 2006)
Optical and X-ray identification of faint radio sources in the GOODS CDF-S
Advanced Camera for Surveys field.
Afonso J., Mobasher B., Koekemoer A., Norris R.P., Cram L.
<Astron. J., 131, 1216-1230 (2006)>
=2006AJ....131.1216A 2006AJ....131.1216A
ADC_Keywords: Active gal. nuclei ; Radio sources ; X-ray sources ; Photometry
Keywords: galaxies: active - galaxies: evolution - galaxies: starburst -
radio continuum: galaxies
Abstract:
We present optical and X-ray identifications for the 64 radio sources
in the Great Observatories Origins Deep Survey (GOODS) in Chandra Deep
Field-South Advanced Camera for Surveys (ACS) field revealed in the
Australia Telescope Compact Array 1.4GHz survey of the Chandra Deep
Field-South. Optical identifications are made using the ACS images and
catalogs, while the X-ray view is provided by the Chandra X-Ray
Observatory 1Ms observations. Redshifts for the identified sources are
drawn from publicly available catalogs of spectroscopic observations
and multiband photometric-based estimates. Using this multiwavelength
information we provide a first characterization of the faint radio
source population in this region.
Description:
The CDF-S was observed at radio (1.4GHz) wavelengths using the
Australia Telescope Compact Array (ATCA). A total of 120hr of
observations were obtained, resulting in a 1.2°2 area field,
covering the CDF-S to a limiting (1σ) sensitivity of ∼14µJy
with a beam size of 16.8"x6.9".
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 127 72 Identification of faint radio sources
table2.dat 118 72 Characterization of faint radio sources
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See also:
II/253 : Chandra Deep Field South: multi-colour data (Wolf+, 2004)
II/261 : GOODS initial results (Giavalisco+, 2004)
J/ApJS/139/369 : Chandra Deep Field South. 1 Ms catalog (Giacconi+, 2002)
J/ApJS/155/271 : Chandra Deep Field-South: Optical spectroscopy
(Szokoly+, 2004)
J/A+A/434/53 : GOODS-South Field redshifts (Vanzella+, 2005)
J/A+A/428/1043 : Redshifts from VIMOS VLT Deep Survey (Le Fevre+, 2004)
J/MNRAS/328/150 : KX redshift survey (Croom+, 2001)
J/A+A/437/883 : K20 survey: spectroscopic catalogue (Mignoli+, 2005)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- [AMK2006] Identification number
3 A1 --- m_[AMK2006] Multiplicity index on [AMK2006]
5- 11 A7 --- --- [ATCDFS_]
12- 30 A19 --- ATCDFS Radio source name (JHHMMSS.ss+DDMMSS.s)
32- 37 F6.3 mJy S1.4GHz The 1.4GHz flux density
39- 43 F5.3 mJy e_S1.4GHz Error in S1.4GHz
45- 63 A19 --- ACS The ACS source name (J2000 position)
65 A1 --- f_ACS [ab] Flag on ACS (1)
67- 70 F4.2 --- Rel ? Reliability of ACS identification
72- 75 F4.1 arcsec rACS ? Distance between radio and ACS positions
77 A1 --- l_zmag Limit flag on zmag
79- 84 F6.3 mag zmag The ACS z850 band (AB) magnitude (2)
86-104 A19 --- CXO The CXO source name
106 A1 --- f_CXO [c] Flag on CXO (3)
108-111 F4.1 arcsec rCXO ? Distance between radio and CXO positions
113 A1 --- l_F0.5-2keV Limit flag on F0.5-2keV
115-119 F5.2 10-18W/m2 F0.5-2keV ? The 0.5-2keV flux
121 A1 --- l_F2-8keV Limit flag on F2-8keV
123-127 F5.2 10-18W/m2 F2-8keV ? The 2-8keV flux
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Note (1): Flag on ACS, defined as follows:
a = Optical sources deblended using SExtractor
b = Optical source not in the released ACS catalogue.
The zmag magnitude results from aperture photometry.
Note (2): z850 is the HST ACS F850LP filter, which correspond to
the SDSS z filter (850nm peak, 945nm centered).
Note (3): A "c" indicates X-ray sources from Giacconi et al. (2002,
Cat. J/ApJS/139/369); the source is denoted by its number in the
catalogue therein, while the flux in the 2-8keV band is an estimate
based on the reported flux in the 2-10keV band and assuming a
power-law photon index of 1.4.
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- [AMK2006] Identification number
3 A1 --- m_[AMK2006] Multiplicity index on [AMK2006]
5- 9 F5.3 --- z ? Spectroscopic redshift
11 A1 --- f_z Flag on zspec (1)
13- 15 F3.1 --- q_z ? Quality flag on zspec (2)
17- 21 F5.3 --- zphC ? COMBO-17 photometric redshift
(Wolf et al. 2004, Cat. II/253)
23- 27 F5.3 --- e_zphC ? Error in zphotC
29- 34 A6 --- CClass COMBO-17 classification (Wolf et al. 2004)
36- 39 F4.2 --- zphM ? Mobasher et al. (2004ApJ...600L.167M 2004ApJ...600L.167M)
photometric redshift
41- 49 A9 --- n_zphM The 95% confidence interval in zphotM
51- 54 F4.2 --- SpType ? Mobasher et al. (2004ApJ...600L.167M 2004ApJ...600L.167M)
best-fit spectral type (3)
56- 57 I2 --- NBand ? Number of bands the source is detected in
Mobasher et al. (2004ApJ...600L.167M 2004ApJ...600L.167M)
59- 63 F5.2 [W/Hz] L1.4GHz ? Log of the 1.4GHz luminosity
65- 69 F5.2 [10-7W] LX ? Log of the 0.5-8keV luminosity in units
of erg/s
71 A1 --- l_R/O Limit flag on R/O
73- 77 F5.2 --- R/O Radio (1.4GHz) to optical flux ratio
79 A1 --- l_X/O Limit flag on X/O
81- 85 F5.2 --- X/O ? X-ray to optical flux ratio
87 A1 --- l_HR Limit flag on HR
89- 93 F5.2 --- HR ? Hardness ratio (4)
95 A1 --- f_HR [b] HR as in Giacconi et al. (2002, Cat.
J/ApJS/139/369) (5)
97 A1 --- l_Gamma Limit flag on Gammma
98-102 F5.2 --- Gamma ? Effective photon index
104 A1 --- f_Gamma [a] Indicates a generic photon index due to
low number of counts
106-109 A4 --- Class X-ray or radio classification (7)
111-118 A8 ---- OClass Optical classification (8)
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Note (1): Flag on z-spec, defined as follows:
s = Spectra from Szokoly et al. (2004, Cat. J/ApJS/155/271);
v = Spectra from Vanzella et al. (2004, Cat. J/A+A/434/53);
l = Spectra from Le Fevre et al. (2004, Cat. J/A+A/428/1043);
c = Spectra from Croom, Warren, & Glazebrook (2001, Cat. J/MNRAS/328/150);
m = Spectra from Mignoli et al. (2005, Cat. J/A+A/437/883).
Note (2): We have converted quality flags from other works to a scale more
similar to the one in Szokoly et al. (2004, Cat. J/ApJS/155/271),
namely: 2.0 denotes a reliable redshift determination, 1.0 indicates
that some spectroscopic feature exists but cannot be securely
identified, and 0.5 flags sources for which there is only a hint
of a spectral feature.
Note (3): Where E=1, Sbc=2, Scd=3, IM=4, and Starburst=5,6.
Note (4): Derived from the 0.5-2 and 2-8keV band counts.
For sources detected only in the Giacconi et al. (2002, Cat.
J/ApJS/139/369) catalogs, we report the quoted hardness ratio,
derived from the 0.5-2keV and 2-10keV band counts.
Note (5): Calculated using the 0.5-2 and 2-10keV bands.
Note (7): Obtained from the X-ray characteristics (LX and/or HR) or,
if possible for sources with insufficient X-ray information, from the
radio power.
Note (8): As in Szokoly et al. (2004, Cat. J/ApJS/155/271), or after
estimating any possible line-emission diagnostic ratios (Sey2 or SF).
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Marianne Brouty [CDS] 16-Jan-2007