10.7.3 Final output

After the filtering and rejection procedure, the second Gaia data release contains 14 099 solar system objects, corresponding to 1 977 702 observations and 287 904 transits. The distribution of the residuals in the AL and AC directions are clearly showed in Figures 10.68 and 10.69. 96% of the AL residuals fall in the interval [-5, 5] and 52% are at sub-mas level. On the other side, almost all the residuals in AC (98%) fall in the interval [-800,800]. The histogram in AC shows a peak around 0, which is related to the distribution of the residuals as a function of the G magnitude: for objects fainter than G=13, the errors in AC are large, while for objects brighter than G=13 the full 2-D window is transmitted and the accuracy in AL and AC are similar (even though the accuracy in AC are still larger).

Figure 10.68: Zoom in the interval [-10, 10] of the AL residuals. There are a few observations (7 304) for which the residuals are larger than 10 mas or smaller than -10 mas. The mean of the AL residuals is 0.05 mas and the standard deviation is 2.14 mas. The two dashed black lines represent the interval [-5, 5], while the two thick blue lines are the boundaries of the interval [-1, 1].
Figure 10.69: Histogram of the AC residuals. The two dashed black lines represent the interval [-800, 800] in which the vast majority of the residuals fall.

The analysis at CCD-level and at transit level and interpretation of asteroid residuals is completely contained in Gaia Collaboration et al. (2018f).