Intervening nuclear obscuration changing the X-ray look of the $z\approx 6$ QSO CFHQS J164121+375520

Fabio Vito, William Nielsen Brandt, Andrea Comastri +16

X-ray observations of the optically selected $z=6.025$ QSO CFHQS J164121+375520 (hereafter J1641) revealed that its flux dropped by a factor $\gtrsim 7$ from 2018, when it was a bri…