Frame Rotator Source

Sources used to compute the Gaia reference frame.The AGIS frame rotator algorithm has two different parts: the reference frame orientation; and the reference frame spin. The reference frame orientation is fixed using the International Earth Rotation and Reference System Service (=IERS) position of a subset of IERS sources defining the third realization of the International Coordinate Reference Frame (Charlot et al., 2020, submitted to A&A), http://hpiers.obspm.fr/icrs-pc/newwww/icrf/index.php. The reference frame spin is defined using the Gaia proper motion of a list of QSOs. The reference frame algorithms have an outliers scheme. Hence for each aspect we provide the considered sources and the used sources actually used, and the number of used sources might be lower than the number of considered sources.