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VLBA Observations of Radio Reference Frame Sources. II. Astrometric Suitability Based on Observed Structure

Published online by Cambridge University Press:  12 April 2016

A. L. Fey
Affiliation:
United States Naval Observatory, Washington, D.C.
P. Charlot
Affiliation:
Paris Observatory, Paris, France

Abstract

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We use source models derived from VLBA observations of 169 extragalactic sources to quantify the expected effects of intrinsic source structure on astrometric bandwidth synthesis VLBI observations. We define a source “structure index” based on the median structure corrections and suggest that this index can be used as an estimate of the astrometric quality of the sources. A correlation between the compactness of the sources and their formal position uncertainties was found indicating that the more extended sources have larger formal position uncertainties.

Type
Research Article
Copyright
Copyright © Astronomical Society of the Pacific 1998

References

Charlot, P. 1990. AJ, 99, 13091326.Google Scholar
Fey, A.L., Clegg, A.W., & Fomalont, E.B. 1996. ApJS, 105, 299330.Google Scholar
Fey, A.L., & Charlot, P. 1997. ApJS, 111, 95142.CrossRefGoogle Scholar
Johnston, K.J., et al. 1995. AJ, 110, 880915.CrossRefGoogle Scholar