Access to Astronomical Catalogues

← Click to display the menu
J/AJ/129/1163         Third VLBA calibrator survey: VCS3         (Petrov+, 2005)

The third VLBA calibrator survey: VCS3. Petrov L., Kovalev Y.Y., Fomalont E., Gordon D. <Astron. J., 129, 1163-1170 (2005)> =2005AJ....129.1163P
ADC_Keywords: Radio sources ; Surveys ; Positional data Keywords: astrometry - catalogs - quasars: general - radio continuum: general - reference systems - techniques: interferometric Abstract: We present the third extension to the Very Long Baseline Array (VLBA) Calibrator Survey, containing 360 new sources not previously observed with Very Long Baseline Interferometry (VLBI). The survey, based on three 24 hour VLBA observing sessions, fills the areas on the sky above declination -45° where the calibrator density is less than one source within a 4° radius disk at any given direction. The positions were derived from astrometric analysis of the group delays determined at 2.3 and 8.6GHz frequency bands using the CALC/SOLVE software package. The VCS3 catalog of source positions, plots of correlated flux density versus length of projected baseline, and contour plots and FITS files of naturally weighted CLEAN images, as well as calibrated visibility function files, are available electronically from the Goddard Geodetic VLBI Group. Description: The VCS3 observations were carried out in three 24hr observing sessions with the VLBA on 2004 April 30, May 8, and May 27. The observations used the VLBA dual-frequency geodetic mode, observing simultaneously at 2.3 and 8.6GHz. Each band was separated into four intermediate-frequency channels, with bandwidth 8MHz which spanned 140MHz at 2.3GHz and 490MHz at 8.6GHz, in order to provide precise measurements of group delays for astrometric processing. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table2.dat 111 360 The VCS3 catalog
See also: VIII/60 : Interferometer phase calibration sources (Patnaik+ 1998) J/ApJS/141/13 : VLBA calibrator Survey - VCS1 catalog (Beasley+, 2002) J/AJ/126/2562 : Second VLBA calibrator survey: VCS2 (Fomalont+, 2003) : VLBA Calibrator Survey 3 (VCS3) Byte-by-byte Description of file: table2.dat
Bytes Format Units Label Explanations
1 A1 --- Cat Source category (1) 3- 10 A8 --- IVS The IVS (Internation VLBI Service for Geodesy and Astrometry) B1950 source name (HHMM+DDd) 12- 21 A10 --- VCS3 Third VLBA Calibrator Survey J2000 source name 23- 24 I2 h RAh Hour of Right ascension (J2000.0) 26- 27 I2 min RAm Minute of Right ascension (J2000.0) 29- 37 F9.6 s RAs Second of Right ascension (J2000.0) 39 A1 --- DE- Sign of the Declination (J2000.0) 40- 41 I2 deg DEd Degree of Declination (J2000.0) 43- 44 I2 arcmin DEm Arcminute of Declination (J2000.0) 46- 53 F8.5 arcsec DEs Arcsecond of Declination (J2000.0) 55- 60 F6.2 mas e_RAs Inflated error in Right Ascension 62- 67 F6.2 mas e_DEs Inflated error in Declination 69- 74 F6.3 --- Corr Correlation between RA and Dec 76- 78 I3 --- Nobs Number of observations used 80 A1 --- l_T8.4GHz [←] flag for T8.4 (2) 81- 84 F4.2 Jy T8.4GHz ? Total VLBA 8.4GHz (X-band) flux density 86 A1 --- l_U8.4GHz [←] flag for U8.4 (2) 87- 90 F4.2 Jy U8.4GHz ? Unresolved VLBA 8.4GHz (X-band) flux density 92 A1 --- l_T2.3GHz [←] flag for T2.3 (2) 93- 96 F4.2 Jy T2.3GHz ? Total VLBA 2.3GHz (S-band) flux density 98 A1 --- l_U2.3GHz [←] flag for U2.3 (2) 99-102 F4.2 Jy U2.3GHz ? Unresolved VLBA 2.3GHz (S-band) flux density 104-106 A3 --- Band Used bands (3) 108-111 A4 --- --- [VCS3] Catalog name
Note (1): Source category: C = calibrator source; - = not a calibrator source. Note (2): Flag on the correlated flux density: - = no data in the following column present. < = upper limit of the flux density is presented in the following column. Note (3): Band code, defined as follows: X/S = ionosphere-free linear combination of X and S wide-band group delays; X = X-band only group delay; S = S-band only group delay.
History: From electronic version of the journal
(End) Greg Schwarz [AAS], Marianne Brouty [CDS] 01-Aug-2005
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

catalogue service