In “LSST/ From Science Drivers to Reference Design and Anticipated Data Products”, there is a Table 3 which lists the astrometric uncertainties for magnitudes 20 and fainter. The text generally describes the process that was used to develop these values. Is there another document that takes this table down to magnitude 17? As a comparison, GAIA shows a 20 fold improvement in astrometric uncertainty from mag 21 to mag 17.
Hi @sdcorle1, thanks for this question.
As described in Section 3.2.1 of Ivezić et al. (2019), the calibration system and procedures are designed to maintain a systematic error component of up to 0.005 magnitudes. In Table 3, the expected photometric error for stars of magnitude 21 and 22 are both 0.005 because for stars that bright, the systematics dominate. I think you can assume similar error, 0.005 mag, for brighter stars.
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