J/MNRAS/385/1656 Extragalactic radio-sources at 95GHz (Sadler+, 2008)
The extragalactic radio-source population at 95GHz.
Sadler E.M., Ricci R., Ekers R.D., Sault R.J., Jackson C.A., De Zotti G.
<Mon. Not. R. Astron. Soc., 385, 1656-1672 (2008)>
=2008MNRAS.385.1656S 2008MNRAS.385.1656S
ADC_Keywords: Radio sources ; Galaxies, radio ; QSOs
Keywords: techniques: interferometric - galaxies: active - quasars: general -
cosmic microwave background - radio continuum: galaxies -
radio continuum: general
Abstract:
We have used the Australia Telescope Compact Array (ATCA) at 95GHz to
carry out continuum observations of 130 extragalactic radio sources
selected from the Australia Telescope 20GHz (AT20G) survey. We use a
triple-correlation method to measure simultaneous 20- and 95-GHz flux
densities for these objects, and over 90 per cent of our target
sources are detected at 95GHz. We demonstrate that the ATCA can
robustly measure 95-GHz flux densities with an accuracy of ∼10 per
cent in a few minutes for sources stronger than about 50mJy.
We measure the distribution of radio spectral indices in a
flux-limited sample of extragalactic sources, and show that the median
20-95GHz spectral index does not vary significantly with flux density
for S20>150mJy . This finding allows us to estimate the
extragalactic radio source counts at 95GHz by combining our observed
20-95GHz spectral-index distribution with the accurate 20-GHz source
counts measured in the AT20G survey.
Description:
The data analysed in this paper were obtained at the Australia
Telescope Compact Array (ATCA) in two observing runs during 2005 July
1-3 and 2006 September 16-19.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table4.dat 140 68 Table of 2005 observations
table5.dat 139 70 Table of 2006 observations
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See also:
VIII/65 : 1.4GHz NRAO VLA Sky Survey (NVSS) (Condon+ 1998)
VIII/81 : Sydney University Molonglo Sky Survey (SUMSS V2.1) (Mauch+ 2008)
Byte-by-byte Description of file: table[45].dat
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Bytes Format Units Label Explanations
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1 A1 --- n_Name [abc] Note on source (1)
3- 11 A9 --- Name Name (HHMM-DDMM)
12 A1 --- f_Name [C*] Calibrator or low-latitude source (2)
14- 15 I2 h RAh Right ascension (J2000)
17- 18 I2 min RAm Right ascension (J2000)
20- 24 F5.2 s RAs Right ascension (J2000)
26 A1 --- DE- Declination sign (J2000)
27- 28 I2 deg DEd Declination (J2000)
30- 31 I2 arcmin DEm Declination (J2000)
33- 36 F4.1 arcsec DEs Declination (J2000)
38- 52 A15 --- OName Alternate name
53 A1 --- l_Bjmag Limit flag on Bjmag
54- 58 F5.2 mag Bjmag ? Blue (BJ) magnitude of the optical
counterpart if any (3)
60 I1 --- T [0/2]? Supercosmos classification of the
optical ID (4)
62 A1 --- l_S95-1 Limit flag on S95GHz1
63- 66 I4 mJy S95-1 ? Flux density at 95GHz, 2005 Day1 or 2006 (5)
68 A1 --- l_S95-2 Limit flag on S95GHz2
69- 72 I4 mJy S95-2 ? Flux density at 95GHz, 2005 Day2 (5)
74- 77 I4 mJy S20-1 ? Flux density at 20GHz, 2005 or 2006 (5)
79- 82 I4 mJy S20-2 ? Flux density at 20GHz, 2004 (6)
84- 86 I3 mJy e_S20-2 ? rms uncertainty on S20GHz2
88- 91 I4 mJy S8.6 ? Flux density at 8.6GHz, 2004 (6)
93- 95 I3 mJy e_S8.6 ? rms uncertainty on S8.6GHz
97-100 I4 mJy S4.8 ? Flux density at 4.8GHz, 2004 (6)
102-104 I3 mJy e_S4.8 ? rms uncertainty on S4.8GHz
106-111 F6.1 mJy S1.4 ? NVSS (Cat. VIII/65) 1.4GHz flux density
113-116 F4.1 mJy e_S1.4 ? rms uncertainty on S1.4GHz
118 A1 --- l_S843 Limit flag on S843MHz
119-124 F6.1 mJy S843 ? SUMSS (Cat. VIII/81) 843MHz flux density
126-130 F5.1 mJy e_S843 ? rms uncertainty on S843MHz
132-137 F6.4 --- z ? Spectroscopic redshift of optical counterpart
139-140 A2 --- ID [QG ? PN] Source class (Quasar, Galaxy, PN)
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Note (1): Flag, for table4 only, as follows:
a = Sources with inverted radio spectra at 5-20GHz
b = Other sources observed but later removed from the
'inverted spectrum' sample
c = Strong sources from the ATCA calibrator list
Note (2): Flag as follows:
C = ATCA calibrator
* = source within 10° of the Galactic plane
Note (3): From Supercosmos catalog (Hambly et al., 2001MNRAS.326.1279H 2001MNRAS.326.1279H).
Note (4): ID as follows:
0 = not classified
1 = galaxy
2 = stellar object (candidate QSO)
Note (5): Simultaneous TCA 95- and 20-GHz flux densities measured in
2005-6 in this project.
Note (6): Near-simultaneous ATCA 20-, 8- and 5-GHz flux densities measured
by the AT20G team in 2004 November. The listed values are from the
2007 July run of the AT20G data pipeline.
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 26-May-2009