VIII/87 The Allen Telescope Array 20cm Survey (ATATS). I. (Croft+ 2010)
The Allen Telescope Array Twenty-centimeter Survey - A 690-square-degree,
12-epoch radio dataset
I. Catalog and long-duration transient statistics
Croft S., Bower G.C., Ackermann R., Atkinson S., Backer D., Backus P.,
Barott W.C., Bauermeister A., Blitz L., Bock D., Bradford T., Cheng C.,
Cork C., Davis M., De Boer D., Dexter M., Dreher J., Engargiola G.,
Fields E., Fleming M., Forster J.R., Gutierrez-Kraybill C., Harp G.,
Helfer T., Hull C., Jordan J., Jorgensen S., Keating G., Kilsdonk T.,
Law C., Van Leeuwen J., Lugten J., MacMahon D., McMahon P., Milgrome O.,
Pierson T., Randall K., Ross J., Shostak S., Siemion A., Smolek K.,
Tarter J., Thornton D., Urry L., Vitouchkine A., Wadefalk N., Welch J.,
Werthimer D., Whysong D., Williams P.K.G., Wright M.
<Astrophys. J., 719, 45-58 (2010)>
=2010ApJ...719...45C 2010ApJ...719...45C
ADC_Keywords: Radio continuum ; Radio sources ; Surveys
Keywords: catalogs - radio continuum: galaxies - surveys
Abstract:
We present the Allen Telescope Array Twenty-centimeter Survey (ATATS),
a multi-epoch (12 visits), 690deg2 radio image and catalog at
1.4GHz. The survey is designed to detect rare, very bright transients
as well as to verify the capabilities of the ATA to form large
mosaics. The combined image using data from all 12 ATATS epochs has
rms noise σ=3.94mJy/beam and dynamic range 180, with a circular
beam of 150" FWHM. It contains 4408 sources to a limiting sensitivity
of 5σ=20mJy/beam. We compare the catalog generated from this 12
epoch combined image to the NRAO VLA Sky Survey (NVSS), a legacy
survey at the same frequency, and find that we can measure source
positions to better than ∼20". For sources above the ATATS
completeness limit, the median flux density is 97% of the median value
for matched NVSS sources, indicative of an accurate overall flux
calibration. We examine the effects of source confusion due to the
effects of differing resolution between ATATS and NVSS on our ability
to compare flux densities. We detect no transients at flux densities
greater than 40mJy in comparison with NVSS and place a 2σ upper
limit of 0.004deg-2 on the transient rate for such sources. These
results suggest that the ≳1Jy transients reported by Matsumara et al.
may not be true transients, but rather variable sources at their flux
density threshold.
Description:
In this paper, we present the ATA Twenty-centimeter Survey (ATATS),
which consists of observations of 690deg2 of sky centered on the
∼10deg2 Bootes deep field. ATATS observations were spread over 12
epochs from 2009 January 12 to April 3. This paper examines the image
and catalog made with data from all 12 epochs and compares it to the
NRAO VLA Sky Survey (NVSS; Condon et al. 1998, Cat. VIII/65).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 59 4408 The ATATS catalog (erratum version: vol.724,
p.827 (2010))
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See also:
VIII/65 : 1.4GHz NRAO VLA Sky Survey (NVSS) (Condon+ 1998)
J/A+A/535/A38 : Observations of NOAO Bootes field at 153MHz (Intema+, 2011)
J/ApJ/716/530 : Mid-IR variability from the SDWFS (Kozlowski+, 2010)
J/AJ/130/923 : Faint radio sources in the NOAO Bootes field (Wrobel+, 2005)
J/AJ/123/1784 : 1.4 GHz imaging of the Bootes field (de Vries+, 2002)
Byte-by-byte Description of file:table2.dat
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Bytes Format Units Label Explanations
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1- 2 I2 h RAh [12/15] Hour of Right Ascension (J2000)
4- 5 I2 min RAm Minute of Right Ascension (J2000)
7- 10 F4.1 s RAs Second of Right Ascension (J2000)
12 A1 --- DE- [+] Sign of Declination (J2000)
13- 14 I2 deg DEd [26/55] Degree of Declination (J2000)
16- 17 I2 arcmin DEm Arcminute of Declination (J2000)
19- 20 I2 arcsec DEs Arcsecond of Declination (J2000)
22- 27 F6.1 mJy S20cm ATATS flux density (20cm)
29- 32 F4.1 mJy bg Background rms
34- 38 F5.1 arcsec amaj Major axis size
40- 44 F5.1 arcsec amin Minor axis size
46- 50 F5.1 deg PA Position angle
52 I1 --- NNVSS [0/4] Number of nearby NVSS sources within
75" of ATATS position
54- 59 F6.1 mJy SNVSS Total NVSS flux density (1.4GHz)
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Nomenclature Notes:
Radio sources are in Simbad (Truncated coordinates in
R.A.).
History:
From electronic version of the journal
References:
Croft et al. Paper II. 2011ApJ...731...34C 2011ApJ...731...34C
(End) Greg Schwarz [AAS] , Emmanuelle Perret [CDS] 08-Jun-2012