Program: GN-2023B-Q-105

Recently a large (>20kpc) and exceptionally luminous (L~2.1x10^43 erg/s) LyAlpha nebula have been discovered around the z=6.6 QSO P323+12. This nebula is potentially tracing an enormous reservoir of cool gas and a rich galactic environment. Which, in agreement with our current understanding of early black hole formation, are necessary conditions to explain rapid growth in both black hole and stellar mass of the first QSOs in the young Universe. We here propose to obtain deep broad and narrow band GMOS observations of this unique target to fully constrain the physical properties of the extended LyAlpha nebula and of the large scale galactic environment. This will enable a detailed characterization of the environment where the first massive galaxies and supermassive black holes can form and evolve and will complement ongoing JWST follow-up.