J/MNRAS/464/3357 GMRT 610-MHz observations of the AMI001 field (Whittam+ 2017)
GMRT 610-MHz observations of the faint radio source population - and what
these tell us about the higher radio-frequency sky.
Whittam I.H., Green D.A., Jarvis M.J., Riley J.M.
<Mon. Not. R. Astron. Soc. 464, 3357 (2017)>
=2017MNRAS.464.3357W 2017MNRAS.464.3357W (SIMBAD/NED BibCode)
ADC_Keywords: Surveys ; Radio sources ; Radio continuum
Keywords: galaxies: active - galaxies: starburst - radio continuum: galaxies
Abstract:
We present 610-MHz Giant Metrewave Radio Telescope observations of
0.84deg2 of the AMI001 field (centred on 00h23m10s, +31d53') with an
rms noise of 18microJy/beam in the centre of the field. A total of 955
sources are detected, and 814 are included in the source count
analysis. The source counts from these observations are consistent
with previous work. We have used these data to study the spectral
index distribution of a sample of sources selected at 15.7GHz from the
recent deep extension to the Tenth Cambridge (10C) survey. The median
spectral index, alpha, (where S∝nu-alpha^) between
0.08<S_15.7GHz/mJy<0.2 is 0.32±0.14, showing that star-forming
galaxies, which have much steeper spectra, are not contributing
significantly to this population. This is in contrast to several
models, but in agreement with the results from the 10C ultra-deep
source counts; the high-frequency sky therefore continues to be
dominated by radio galaxies down to S15.7GHz=0.1mJy.
Description:
GMRT 610-MHz source catalogue, containing 955 components. 151
components are flagged as being part of a group.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 109 955 Source catalogue of 955 sources
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Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 13 A13 --- Source Source name (HHMMSS+DDMMSS)
15- 31 A17 --- Group Group designation (group name followed by the
number of components in the group in brackets)
33- 34 I2 h RAh Peak right ascension (J2000)
36- 37 I2 min RAm Peak right ascension (J2000)
39- 43 F5.2 s RAs Peak right ascension (J2000)
45 A1 --- DE- Peak declination sign (J2000)
46- 47 I2 deg DEd Peak declination (J2000)
49- 50 I2 arcmin DEm Peak declination (J2000)
52- 56 F5.2 arcsec DEs Peak declination (J2000)
58- 64 F7.3 mJy Spk Peak flux density at 610MHz
66- 70 F5.3 mJy e_Spk Error in peak flux density
72- 78 F7.3 mJy Sint Integrated flux density at 610MHz
80- 85 F6.3 mJy e_Sint ?=-1 Error in integrated flux density
87- 90 F4.1 arcsec maj ?=-1 Deconvolved source major axis
92- 95 F4.1 arcsec min ?=-1 Deconvolved source minor axis
97-101 F5.1 deg theta ?=-1 Deconvolved position angle,
measured from North to East
103-107 F5.3 mJy/beam Noise Local rms noise
109 A1 --- Type [-EP] Source type (1)
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Note (1): Source type as follows:
P = point source
E = extended source
- = fitting failed, unclassified
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Acknowledgements:
Imogen Whittam, imogenwhittam(at)gmail.com
(End) Imogen Whittam [UWC], Patricia Vannier [CDS] 27-Jan-2017