NASA/IPAC EXTRAGALACTIC DATABASE
Date and Time of the Query: 2019-06-19 T01:22:47 PDT
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For refcode 1997ApJS..111...95F:
Retrieve 133 NED objects in this reference.
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Copyright by American Astronomical Society. Reproduced by permission
1997ApJS..111...95F VLBA Observations of Radio Reference Frame Sources. II. Astrometric Suitability Based on Observed Structure ALAN L. FEY US Naval Observatory, Code EO, 3450 Massachusetts Avenue, NW, Washington, DC 20392-5420; afey@alf.usno.navy.mil AND PATRICK CHARLOT Observatoire de Paris, CNRS/URA 1125, 61 avenue de l'Observatoire, F- 75014 Paris, France; charlot@obspm.fr Received 1996 December 2; accepted 1997 January 14 ABSTRACT We present simultaneous dual-frequency Very Long Baseline Array 2 and 8 GHz observations of 133 of the 560 extragalactic sources for which positions were reported by Johnston et al. These observations represent the second in a series of observations intended to image the entire set of sources presented by Johnston et al. and, together with previously reported observations, bring the total number of sources observed so far to 169. We use the data to quantify the magnitude of the expected effect of intrinsic source structure on astrometric bandwidth synthesis VLBI observations. We also define a source "structure index," which can be used as an estimate of the astrometric quality of the sources. Subject headings: quasars: general-radio continuum: galaxies -surveys
Retrieve 133 NED objects in this reference.
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