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J/ApJS/141/13       VLBA calibrator survey: VCS1 catalog    (Beasley+, 2002)

The VLBA calibrator Survey - VCS1. Beasley A.J., Gordon D., Peck A.B., Petrov L., MacMillan D.S., Fomalont E.B., Ma C. <Astrophys. J. Suppl. Ser. 141, 13 (2002)> =2002ApJS..141...13B
ADC_Keywords: Radio sources ; Surveys ; Positional data Keywords: astrometry - radio continuum: general - reference systems - surveys - techniques: interferometric Abstract: A catalog containing milli-arcsecond-accurate positions of 1332 extragalactic radio sources distributed over the northern sky is presented - the Very Long Baseline Array Calibrator Survey (VCS1). The positions have been derived from astrometric analysis of dual-frequency 2.3 and 8.4 GHz VLBA snapshot observations; in a majority of cases, images of the sources are also available. These radio sources are suitable for use in geodetic and astrometric experiments, and as phase-reference calibrators in high-sensitivity astronomical imaging. The VCS1 is the largest high-resolution radio survey ever undertaken and triples the number of sources available to the radio astronomy community for VLBI applications. In addition to the astrometric role, this survey can be used in active galactic nuclei, Galactic, gravitational lens, and cosmological studies. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table2.dat 108 1332 VCS1 Catalog table4.dat 108 72 VCS1 ICRF-Ext.1 source catalog table3.dat 10 126 *Sources not used in the astrometric solution
Note on table3.dat: Sources not detected at either band, or yielding only one measurement of group delay
See also: VIII/60 : Interferometer phase calibration sources (Patnaik+ 1998) Byte-by-byte Description of file: table2.dat table4.dat
Bytes Format Units Label Explanations
1- 10 A10 --- VCS1 The VCS1 J2000.0 source name (JHHMM+DDMM) 12- 21 A10 --- IVS The IVS (International VLBI Service for Geodesy and Astrometry) B1950 source name (HHMM+DDd) 22- 23 I2 h RAh Hour of Right ascension (J2000) 25- 26 I2 min RAm Minute of Right ascension (J2000) 28- 36 F9.6 s RAs Second of Right ascension (J2000) 38 A1 --- DE- Sign of the Declination (J2000) 39- 40 I2 deg DEd Degree of Declination (J2000) 42- 43 I2 arcmin DEm Arcminute of Declination (J2000) 45- 52 F8.5 arcsec DEs Arcsecond of Declination (J2000) 55- 63 F9.4 mas e_RAs Inflated formal error in Right ascension 65- 72 F8.4 mas e_DEs Inflated formal error in Declination 74- 79 F6.4 --- Corr Correlation between right ascension and declination error estimates (1) 81- 87 I7 --- Num Number of observations used from survey sessions 89- 94 A6 --- BCode Band code (2) 96-108 A13 --- CName Catalogue name (vcs1 or ext1-est)
Note (1): The greater the amplitude of the correlation, the higher the eccentricity of the error ellipse for this source. Note (2): Band code: X/S = Solution incorporates both 2.3 & 8.4GHz group delays. X-only = Solution incorporates only 8.4GHz group delays. X+ = Solution incorporates only 8.4GHz group delays; 2.3GHz group delays were available, but the number of 2.3GHz group delays was significantly less than the number of 8.4GHz group delays.
Byte-by-byte Description of file: table3.dat
Bytes Format Units Label Explanations
1- 10 A10 --- JVAS JVAS J2000 Source Name
History: * 09-Jul-2002: From electronic version of the journal * 30-Jul-2003: J2126-0191 corrected in J2126-0119 in table2 2134+00 corrected in 2134+004 in table4
(End) Greg Schwarz [AAS], Patricia Bauer [CDS] 09-Jul-2002
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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