J/MNRAS/490/243 ELAIS N1 field uGMRT 400MHz source catalog (Chakraborty+, 2019)
Detailed study of ELAIS N1 field with the uGMRT.
II. Source properties and spectral variation of foreground power spectrum from
300-500 MHz observations.
Chakraborty A., Roy N., Datta A., Choudhuri S., Datta K.K., Dutta P.,
Bharadwaj S., Intema H., Choudhury M., Pal S., Choudhury T.R.
<Mon. Not. R. Astron. Soc. 490, 243-259 (2019)>
=2019MNRAS.490..243C 2019MNRAS.490..243C (SIMBAD/NED BibCode)
ADC_Keywords: Surveys ; Galaxies, radio ; Morphology
Keywords: cosmology - diffuse emission - interferometric - surveys - galaxies
Abstract:
Understanding the low-frequency radio sky in depth is necessary to
subtract foregrounds in order to detect the redshifted 21 cm signal of
neutral hydrogen from the cosmic dawn, the epoch of reionization and
the post-reionization era. In this second paper of the series, we
present the upgraded Giant Metrewave Radio Telescope (uGMRT)
observation of the ELAIS N1 field made at 300-500MHz. The image
covers an area of ∼1.8deg2 and has a central background rms noise
of ∼15uJy/beam. We present a radio source catalogue containing 2528
sources (with flux densities >100uJy) and normalized source counts
derived from that. A detailed comparison of detected sources with
previous radio observations is shown. We discuss flux-scale accuracy,
positional offsets, spectral index distribution and correction factors
in source counts. The normalized source counts are in agreement with
previous observations of the same field, as well as model source
counts from the Square Kilometre Array Design Study simulation. It
shows a flattening below ∼1mJy that corresponds to a rise in
populations of star-forming galaxies and radio-quiet active galactic
nuclei. For the first time, we estimate the spectral characteristics
of the angular power spectrum or multi-frequency angular power
spectrum of diffuse Galactic synchrotron emission over a wide
frequency bandwidth of 300-500MHz from radio interferometric
observations. This work demonstrates the improved capabilities of the
uGMRT.
Description:
The catalog of sources detected in ELAIS N1 filed at 400MHz using
uGMRT widebandwidth data.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
catalog.dat 100 2528 uGMRT 400MHz source catalogue for the
ELAIS N1 field
ELAISN1400MHz.fits 2880 94 fits version of the 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)
J/MNRAS/395/269 : ELAIS-N1 field 325MHz observations (Sirothia+, 2009)
J/ApJ/714/1689 : DRAO ELAIS N1 catalog (Grant+, 2010)
J/ApJ/762/93 : PiGSS. III. ELAIS-N1, Coma + Lockman fields (Croft+, 2013)
J/MNRAS/472/4259 : IRAC Dark Field, ELAIS-N1 & ADF-S galaxies (Davidge+, 2017)
Byte-by-byte Description of file: catalog.dat
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Bytes Format Units Label Explanations
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1- 4 I4 --- ID [0/2528] Sequential number
6- 15 F10.6 deg RAdeg Right ascension (J2000)
17- 22 F6.4 arcsec e_RAdeg Error in Right ascension (J2000)
24- 32 F9.6 deg DEdeg Declination (J2000)
34- 39 F6.4 arcsec e_DEdeg Error in Declination
41- 48 F8.4 mJy TotalFlux Flux density at 400MHz
50- 56 F7.4 mJy e_TotalFlux Error in flux density
58- 65 F8.4 mJy/beam PeakFlux Peak flux at 400MHz
67- 73 F7.4 mJy/beam e_PeakFlux Error in peak flux
75- 79 F5.2 arcsec Major Major axis of source
81- 85 F5.2 arcsec Minor Minor axis of source
87- 93 F7.3 deg PA Position angle
95-100 F6.4 mJy/beam rms rms value
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Acknowledgements:
Arnab Chakraborty, phd1601121009(at)iiti.ac.in
History:
12-Nov-2019: on-line version
30-Mar-2020: Precision in RA, DE increased
(End) Patricia Vannier [CDS] 11-Nov-2019