A Practical Guide to the Massive Black Hole Cosmic History
Figure 4
The GW landscape. A representative summary of GW observations of MBH binaries with PTAs (through the detection of a GW stochastic background) and NGO (via the direct detection the final stage of the coalescence of individual binary systems). In the main panel, we show the characteristic amplitude of GW signals as a function of frequency, compared to the sensitivity of SKA and NGO. On the left side, we show a Montecarlo realization of the GW signal coming from a cosmological population of MBH binaries: green dots represent the strain of each individual source, the overall signal is shown as a blue solid line, individually resolvable sources are shown as blue triangles, and unresolved background is shown as a green solid line. On the right side, red lines track the inspiral of selected MBH binaries at . The upper right panel shows the massive black hole binary coalescence rate as a function of the total mass for two representative MBH population models. The green- and red-shaded areas highlight the portion of the mass function that will be probed by PTA and NGO, respectively, highlighting the complementarity of the two probes.
