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arXiv · 1403.1717

On the impact of correlation information on the orientation parameters between celestial reference frame realizations

Yulia Sokolova·Zinovy Malkin
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Abstract

In this study, we compared results of determination of the orientation angles between celestial reference frames realized by radio source position catalogues using three methods of accounting for correlation information: using the position errors only, using additionally the correlations be-tween the right ascension and declination (RA/DE correlations) reported in radio source position catalogues published in the IERS format, and using the full covariance matrix. The computations were performed with nine catalogues computed at eight analysis centres. Our analysis has shown that using the RA/DE correlations only slightly influences the computed rotational angles, whereas using the full correlation matrices leads to substantial change in the orientation parameters be-tween the compared catalogues.

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Yulia Sokolova, Zinovy Malkin. 2014-03-07. On the impact of correlation information on the orientation parameters between celestial reference frame realizations. https://doi.org/10.1007/1345_2015_179

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