The total readnoise levels of GAIA CCDs in the ASM1 and in the BBPs of the
Astros can be estimated following the recipe of [Vannier 1999].
The values obtained for the presently planned sampling of the ASM1
are given together with the values obtained for four different sample sizes
in the BBPs in Table 5.2.
Even though the sample size in the ASM1 appears fairly well-established,
the values obtained for different sample sizes in the ASM1 are also
included to illustrate how a decrease in the required accuracy of
two-dimensional position measurements in the ASM would result in a substantial
reduction of the readnoise.