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Table 9.

Number of ICRF3 defining sources at each frequency band and statistics about coordinate uncertainties, correlation coefficients between right ascension and declination, and the error ellipse size (semi-major axis) for these sources.

Statistics for all defining sources
Statistics for the common defining sources
Frequency Number of Coordinate uncertainty Correlation Error ellipse Coordinate uncertainty Correlation Error ellipse
band sources α cos δ δ coeff. (μas) α cos δ δ coeff. (μas)
(μas) (μas) (μas) (μas)
S/X 303 36 41 0.07 41 33 35 0.06 35
K 193 63 120 0.28 122 60 113 0.27 115
X/Ka 176 62 92 0.40 98 62 92 0.40 97

Notes. Statistics are provided for all defining sources in each catalog and for the 171 defining sources common to the three catalogs. All values reported in columns 3–10 are median values.

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