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J/MNRAS/460/4433      SDSS Stripe 82 VLA 1-2GHz survey          (Heywood+, 2016)

A deep/wide 1-2 GHz snapshot survey of SDSS Stripe 82 using the Karl G. Jansky Very Large Array in a compact hybrid configuration. Heywood I., Jarvis M.J., Baker A.J., Bannister K.W., Carvalho C.S., Hardcastle M., Hilton M., Moodley K., Smirnov O.M., Smith D.J.B., White S.V., Wollack E.J. <Mon. Not. R. Astron. Soc., 460, 4433-4452 (2016)> =2016MNRAS.460.4433H (SIMBAD/NED BibCode)
ADC_Keywords: Surveys ; Radio sources ; Morphology Keywords: surveys - radio continuum: general Abstract: We have used the Karl G. Jansky Very Large Array to image ∼100deg2 of SDSS Stripe 82 at 1-2GHz. The survey consists of 1026 snapshot observations of 2.5-min duration, using the hybrid CnB configuration. The survey has good sensitivity to diffuse, low surface brightness structures and extended radio emission, making it highly synergistic with existing 1.4GHz radio observations of the region. The principal data products are continuum images, with 16x10 arcsec resolution, and a catalogue containing 11782 point and Gaussian components resulting from fits to the thresholded Stokes-I brightness distribution, forming approximately 8948 unique radio sources. The typical effective 1σ noise level is 88µJy/beam. Spectral index estimates are included, as derived from the 1GHz of instantaneous bandwidth. Astrometric and photometric accuracy are in excellent agreement with existing narrowband observations. A large-scale simulation is used to investigate clean bias, which we extend into the spectral domain. Clean bias remains an issue for snapshot surveys with the VLA, affecting our total intensity measurements at the ∼1σ level. Statistical spectral index measurements are in good agreement with existing measurements derived from matching separate surveys at two frequencies. At flux densities below ∼35σ the median in-band spectral index measurements begin to exhibit a bias towards flatness that is dependent on both flux density and the intrinsic spectral index. In-band spectral curvature measurements are likely to be unreliable for all but the very brightest components. Image products and catalogues are publicly available via an FTP server ( Description: The data (Project code: 13B-272) were taken with the array in the CnB configuration. Standard wide-band mode was employed with the correlator splitting the 1-2GHz of frequency coverage into 16 spectral windows (SPWs) with 64x1MHz channels each, and an integration time per visibility point of 3s. A total of 1368 target pointings were scheduled, 608 and 760 in the eastern and western regions, respectively, coincident with the two eastern and western areas of the existing Hodge et al. (2011, Cat. J/AJ/142/3) data. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table1e.dat 155 5674 Eastern catalogue table1w.dat 155 6094 Western catalogue
See also: J/AJ/142/3 : 1.4GHz observations of Stripe 82 (Hodge+, 2011) Byte-by-byte Description of file: table1e.dat table1w.dat
Bytes Format Units Label Explanations
1- 16 A16 --- ID Identifier (JHHMMSS.s+DDMMSS) 18- 26 F9.5 deg RAdeg Right ascension (J2000) 28- 35 F8.5 deg DEdeg Declination (J2000) 37- 40 F4.2 arcsec e_RAdeg 1σ uncertainty in RA 42- 45 F4.2 arcsec e_DEdeg 1σ uncertainty in DE 47- 54 F8.3 mJy Sint Integrated flux density at 1-2GHz 56- 60 F5.3 mJy e_Sint 1σ uncertainty in Sint 62- 69 F8.3 mJy/beam Speak Peak flux density at 1-2GHz 71- 75 F5.3 mJy/beam e_Speak 1σ uncertainty in Speak 77- 81 F5.1 uJy/beam rms Estimate of the local RMS noise at the position of the component 83- 89 F7.3 --- alpha Spectral index (1) 91- 97 F7.4 arcsec Maj ?=0 Deconvolved major-axis size of the Gaussian fitted to the component (2) 99-105 F7.4 arcsec e_Maj ?=0 1σ uncertainty in Maj 107-113 F7.4 arcsec Min ?=0 Deconvolved minor-axis size of the Gaussian fitted to the component (2) 115-120 F6.4 arcsec e_Min ?=0 1σ uncertainty in Min 122-129 F8.4 deg PA ?=0 Position angle measured east of north of the Gaussian fitted 131-138 F8.4 deg e_PA ?=01σ uncertainty in PA 140 I1 --- Res [0/1] flag to indicate whether or not the component is likely to be reliably spatially resolved, i.e. does the component lie above the upper envelope on Fig. 13. 142-145 I4 --- IDg Zero-indexed unique identifier for the component 147-150 I4 --- IDs Zero-indexed unique identifier for the source 152-155 I4 --- IDi Zero-indexed unique identifier for the island
Note (1): formed from an error-weighted mean of the pixel values in the spectral index mosaic over the extent of the component, or the extent of the survey restoring beam, whichever is larger. Note (2): A value of zero indicates that the source finder was unable to determine the intrinsic size, and the component is indistinguishable from being point-like.
History: From electronic version of the journal
(End) Patricia Vannier [CDS] 24-Nov-2017
The document above follows the rules of the Standard Description for Astronomical Catalogues.From this documentation it is possible to generate f77 program to load files into arrays or line by line

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