Joint Astrophysical Colloquium
Multiphase gas reservoirs around z~3 quasars and the impact of AGN feedback from galaxy to halo scales
Fabrizio Arrigoni Battaia (MPA Munich)
Thursday 13/11/2025 @ 11:30, Sala Antonio Sollima (IV piano Battiferro)
The systematic targeting of high-redshift quasars using narrow-band imaging and the new generation of integral-field unit spectrographs has enabled the routine detection of extended Lyman-alpha emission on scales of hundreds of kiloparsecs. These structures trace the cool gas reservoirs that funnel down onto massive galaxies and ultimately sustain the activity of their central supermassive black holes. In this talk, I will present the results of the QSOMUSEUM survey, which has thus far observed the circumgalactic medium of 120 z~3 quasars using the VLT/MUSE instrument. The survey covers the full luminosity range of SDSS quasars, providing sufficient statistics to begin marginalising over quasar physical properties (e.g. black hole mass) and witnessing the impact of AGN feedback on halo scales. I will also report on ALMA observations of the CO(4-3) transition from a subset of these quasars. These data probe the molecular gas reservoir on few kpc and provide additional evidence of AGN feedback. Together, these efforts demonstrate the need for statistical, multi-wavelength and multi-scale observations to improve our understanding of the baryon cycle around quasars, from their host galaxies to their surrounding environments.