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1991ApJS...75....1Becker
A new catalog of 53522 4.85 GHZ sources
Becker, R. H., White, R. L., and Edwards, A. L.
Abstract
A catalog of 53522 4.85 GHz sources between 0 and 75^o declination has been
generated from observation taken with the NRAO Green Bank 300 foot (91m)
telescope. The flux limit of the catalog is dependent on confidence radius
of ~50". Spectral indices have been calculated for 29051 sources which have
counterpart in the Texas 365 MHz northern sky survey.
Catalog constuction
The observations were made in 1987 October. The resulting data were gridded
into 285 1024x1024 FITS imagis with 40" pixel size. The rms noise in the
images varied from 5 to 8 mJy. The images has an angular resolution of ~3.5'.
Sources with peak fluxes brighter than 70 Jy were truncated in the images,
so they usually have been omitted from our catalog.
The extraction of the source catalog from the images limited smaller
than ~5' in diameter. All source identification were based on high filtered
images (each pixel - surrounding 15 x 15 pixel area median value).
The catalog of 53522 sourecs is given in Tables 3 - 5 for the declination
40, 20 - 40 and 20^o. There are 3279 extended sources in the catalog.
Distribution version, 4 September 1990
This is a brief description of the format of the distribution version of
the 6 cm Northern Sky Catalog of Becker, R. H., White, R. L., and
Edwards, A. L. (1991, Ap.J.Suppl., 75, 1). For more details see
the paper.
The catalog is in an ascii file with 44 characters per record. It can
be read with the following Fortran statements:
character name*10, decsgn*1, extflg, widflg
integer rahh, ramm, decdd, decmm, decss, flux
real rass, spind
read(10,1) name, rahh, ramm, rass, decsgn, decdd, decmm, decss,
& flux, extflg, spind, widflg
1 format(a10,1x,i2, 1x, i2, 1x, f4.1, 1x, a1, i2, 1x, i2, 1x, i2,
& i6, a1, 1x, f4.1, a1)
Column Variable Format Description
------ -------- ------ -----------
(1) NAME A10 6cm Name, constructed from RA, Dec HHMM+DDMM with
A or B added at end if needed to make name unique
(2) RAHH I2 Hours of right ascension (1950)
(3) RAMM I2 Minutes of RA
(4) RASS F4.1 Seconds of RA
(5) DECSGN I2 Sign of declination
(6) DECDD I2 Degrees of declination
(7) DECMM I2 Minutes of declination
(8) DECSS I2 Seconds of declination
(9) FLUX I6 4.85 GHz flux (mJy)
(10) EXTFLG A1 "*" if source is extended, else blank
(11) SPIND F4.1 Spectral index between 4.85 GHz and 0.365 GHz (flux
from Texas survey, Douglas et al., private comm.),
blank if not detected at 0.365 GHz
(12) WIDFLG A1 "*" if separation between 4.85 GHz and 0.365 GHz
positions is greater than 100 arcsec, else blank
Here are a few sample lines from the catalog:
123456789 123456789 123456789 123456789 1234
Name HH MM SS.S SDD MM SS FFFFFE SS.SW
0000+1833 00 00 4.0 +18 33 23 66 -0.9
0000+1549 00 00 5.9 +15 49 12 72
0000+7459 00 00 17.5 +74 59 18 47
0000+5729 00 00 42.8 +57 29 16 64 -0.7*
0001+0343 00 01 6.5 +03 43 20 107*
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