- High Precision Astrometry with Closure Constraints,
E. Ros, J. M. Marcaide, J. C. Guirado, M. I. Ratner, I. I. Shapiro,
T. P. Krichbaum, A. Witzel, & R. A. Preston,
IAU Colloquim 164: Radio Emission from Galactic and Extragalactic
Compact Sources, eds. J. A. Zensus, G. B. Taylor, & J. M. Wrobel,
ASP Conference Series Vol. 144, pp. 389-390, (1998)
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- Abstract
We determine the relative separations of the sources in the triangle
1803+784/1928+738/2007+777 with submilliarcsecond accuracy from
global 8.4 GHz VLBI observations. We remove the ionospheric
contribution to the phase-delay observable using ionospheric total
electron content estimates obtained from Global Positioning System
(GPS) data. The triangular geometry provides a consistency check
through sky closure.
Eduardo Ros
