J/MNRAS/395/269 ELAIS-N1 field 325MHz observations (Sirothia+, 2009)
325-MHz observations of the ELAIS-N1 field using the giant metrewave
radio telescope.
Sirothia S.K., Dennefeld M., Saikia D.J., Dole H., Ricquebourg F.,
Roland J.
<Mon. Not. R. Astron. Soc., 395, 269-281 (2009)>
=2009MNRAS.395..269S 2009MNRAS.395..269S
ADC_Keywords: Surveys ; Galaxies, radio
Keywords: catalogues - surveys - radio continuum: galaxies - galaxies: active
Abstract:
We present observations of the European Large-Area ISO Survey-North 1
(ELAIS-N1) at 325MHz using the Giant Metrewave Radio Telescope (GMRT),
with the ultimate objective of identifying active galactic nuclei and
starburst galaxies and examining their evolution with cosmic epoch.
After combining the data from two different days we have achieved a
median rms noise of ∼40uJy/beam, which is the lowest that has been
achieved at this frequency. We detect 1286 sources with a total flux
density above ∼270uJy. In this paper, we use our deep radio image to
examine the spectral indices of these sources by comparing our flux
density estimates with those of Garn et al. 2008 (Cat. J/MNRAS/383/75)
at 610MHz with the GMRT, and surveys with the Very Large Array at
1400MHz. We attempt to identify very steep spectrum sources which are
likely to be either relic sources or high-redshift objects as well as
inverted-spectra objects which could be Giga-Hertz Peaked Spectrum
objects. We present the source counts, and report the possibility of a
flattening in the normalized differential counts at low flux densities
which has so far been reported at higher radio frequencies.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3.dat 81 1285 The source catalog
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See also:
II/255 : SWIRE ELAIS N1 Source Catalogs (Surace+, 2004)
J/AJ/129/1198 : SDSS quasars in SWIRE ELAIS N1 field (Hatziminaoglou+, 2005)
J/MNRAS/371/1891 : GOODS ELAIS-N1 24um flux densities (Rodighiero+, 2006)
J/ApJ/666/201 : Radio polarimetry of the ELAIS N1 field (Taylor+, 2007)
J/MNRAS/383/75 : Deep 610MHz survey of ELAIS-N1 sources (Garn+, 2008)
Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 4 A4 --- --- [GMRT]
5- 17 A13 --- GMRT GMRT source name (HHMMSS+DDMMSS),
[SDS2009] GMRT JHHMMSS+DDMMSS in Simbad
19- 20 I2 h RAh Right ascension (J2000) (1)
22- 23 I2 min RAm Right ascension (J2000) (1)
25- 28 F4.1 s RAs Right ascension (J2000) (1)
30 A1 --- DE- Declination sign (J2000) (1)
31- 32 I2 deg DEd Declination (J2000) (1)
34- 35 I2 arcmin DEm Declination (J2000) (1)
37- 40 F4.1 arcsec DEs [0/69] Declination (J2000) (1)
42- 45 F4.2 deg Dist Distance of the centroid from the phase
center
47- 50 I4 uJy rms Local rms noise value (in µJy/beam)
52- 58 F7.2 mJy Sp 325MHz peak flux density (in mJy/beam)
60- 66 F7.2 mJy Stot3 325MHz total flux density within
the 3σ contour
68- 74 F7.2 mJy Stot 325MHz total flux density
76- 80 F5.1 arcsec Size ? Largest angular size for resolved source
81 A1 --- Note [U] U for unresolved source
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Note (1): Position of the source, which is the flux-density weighted
centroid of all the emission enclosed by the 3σ contour.
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 30-Jul-2010