Table 1
Single source statistics in Case A.
| α = 0 | α = 1 | α = 2 | α = 3 | α = 4 | |
|
|
|||||
| ω = 1.00 | |||||
| S 5,n | +0.0536 | +0.0215 | +0.0129 | +0.0094 | +0.0078 |
| α ∗ | +0.0504 | +0.0184 | +0.0099 | +0.0065 | +0.0049 |
| δ | +0.0497 | +0.0178 | +0.0093 | +0.0059 | +0.0044 |
| ϖ | +0.0553 | +0.0232 | +0.0148 | +0.0116 | +0.0102 |
| μα ∗ | +0.0559 | +0.0238 | +0.0150 | +0.0114 | +0.0097 |
| μδ | +0.0539 | +0.0218 | +0.0130 | +0.0096 | +0.0079 |
|
|
|||||
| ω = 1.16 | |||||
| S5,n | +0.0536 | +0.0166 | +0.0051 | −0.0002 | −0.0030 |
| α ∗ | +0.0504 | +0.0135 | +0.0021 | −0.0031 | −0.0058 |
| δ | +0.0497 | +0.0128 | +0.0015 | −0.0036 | −0.0063 |
| ϖ | +0.0553 | +0.0183 | +0.0071 | +0.0022 | −0.0004 |
| μα ∗ | +0.0559 | +0.0188 | +0.0071 | +0.0017 | −0.0013 |
| μδ | +0.0539 | +0.0168 | +0.0052 | −0.0001 | −0.0030 |
Notes. S5,n is the statistic testing the 5 × 5 covariance matrices of the n sources at different levels of approximation (α). The subsequent lines give the statistic S1,n for the different astrometric parameters. The number of sources considered is n = 3 × 105 which gives an uncertainty of ± 0.0012 for S5,n and ± 0.0026 for S1,n. Results are given for two values of the fudge factor ω. The results for α = 0 are unaffected by the value of ω, because the attitude variance is not taken into account in the zero-order approximation.
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