The QUBRICS Survey

Finding the brightest QSOs at high-z is important both for constraining cosmic evolution and fundamental physics. However, in the Southern Hemisphere, the number of bright QSOs is still relatively scarce. The advent of recent databases, including SkyMapper, Gaia, DESI, offers a golden opportunity to fill in this gap. The QUBRICS survey (QUasars as BRIght beacons for Cosmology in the Southern hemisphere) has been active since 2019, exploiting these databases through machine learning techniques (e.g. CCA, PRF, XGB) and so far over 400 new, bright (i < 18) and high-redshift (z > 2.5) QSOs have been spectroscopically confirmed. In this poster we highlight some of the multiple scientific applications enabled by such a dataset like (i) improving the estimate of the luminosity function; (ii) analyzing absorption features along the line of sight and (iii) improving the performance of the selection algorithms. In the future, QSOs confirmed by this survey will be the targets of subsequent studies using higher resolution spectrographs like MIKE, ESPRESSO, WINERED and will be prime targets for foreground galaxy redshift surveys with LLAMAS.