Table 8.
Major features of ICRF3, including the number of 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).
| Statistics for all sources |
Statistics for the common 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 | 4536 | 127 | 218 | 0.13 | 223 | 48 | 64 | 0.08 | 64 |
| K | 824 | 74 | 136 | 0.30 | 139 | 68 | 132 | 0.31 | 135 |
| X/Ka | 678 | 76 | 104 | 0.43 | 115 | 69 | 100 | 0.44 | 108 |
Notes. Statistics are provided for the entire S/X, K, and X/Ka band catalogs and for the subset of 600 sources common to the three catalogs. All values reported in columns 3–10 are median values.
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