092270

Rapidly accreting QSOs are unique laboratories to understand supermassive blackhole growth and AGN feedback. Recent observations show that surprisingly thesesources do not differ much from slowly accreting QSOs. Some of these sourcesshow a unexpected variability notably in X-rays. Results from eROSITA and ourrecent monitoring of SMSS J1144 (z=0.83 log M/Msun = 9.4 Lbol/LEdd = 1.4) show that this QSO is highly variable on timescales ranging from weeks to a fewmonths. We propose a Swift monitoring of the source that will allow us totrigger two XMM-Newton + NuSTAR ToO to catch the source in the low- andhigh-flux states. This will allow us to better measure the properties of thesource identify signs of reflection and feedback and understand the origin of the unusual variability. [truncated! Please see actual data for full text]