On the hunt for supermassive black hole binaries with Pulsar Timing Arrays.

Pulsar timing arrays, which probe nanohertz-frequency gravitational waves, have recently reported the very first evidence for the presence of a stochastic background. This background most likely originates from a superposition of inspiraling supermassive black hole binaries. However, more speculative sources such as cosmic strings and phase transitions cannot be ruled out. As we may now be entering the detection era, pulsar timing arrays will focus on identifying and characterising the source of the signal. 

In the talk I will review the recent efforts of the pulsar timing community towards understanding the emerging signal. In particular, I will show how this goal can be targeted from many different angles, starting from radio data acquisition and analysis up to multi-messenger astrophysical studies in the context of galaxy evolution.