The descendants of the first quasars in the BlueTides simulation

Supermassive blackholes with masses of a billion solar masses or more are known to exist up to z = 7. However, the present-day environments of the descendants of first quasars are not well understood and it is not known if they live in massive galaxy clusters or more isolated galaxies at z = 0. We use a dark matter-only realization (BTMassTracer) of the BlueTides cosmological hydrodynamic simulation to study the halo properties of the descendants of the most massive black holes at z = 8. We find that the descendants of the quasars with most massive black holes are not amongst the most massive haloes. They reside in haloes of with group-like (similar to 10(14) M-circle dot) masses, while the most massive haloes in the simulations are rich clusters with masses similar to 10(15) M-circle dot. At z = 0, the distribution of halo masses of these quasar descendants is similar to that of the descendants of least massive black holes, which indicates that they are likely to exist in similar environments. By tracing back to the z = 8 progenitors of the most massive (cluster sized) haloes at z = 0; we find that their most likely black hole mass is less than 10(7) M-circle dot; they are clearly not amongst the most massive black holes. For haloes above 10(15) M-circle dot, there is only 20 per cent probability that their z = 8 progenitors hosted a black hole with mass above 10(7) M-circle dot.