An X-ray fading, UV brightening QSO at $z\approx 6$

Fabio Vito, Marco Mignoli, Roberto Gilli +13

Explaining the existence of $\gtrsim 10^8{\mathrm{M}}_{\odot }$ SMBHs at $z>6$ is a persistent challenge to modern astrophysics. Multi-wavelength observations of $z\gtrsim 6$ QSOs revea…