Efficient Large-Scale, Targeted Gravitational-Wave Probes of Supermassive Black-Hole Binaries.

Binary systems of supermassive black holes are promising sources of low-frequency gravitational waves (GWs) and bright electromagnetic emission. Pulsar timing array GW searches for individual binaries have been limited to only a few candidate systems due to computational demands, which get worse as more pulsars are added. By modeling the GW signal using only components from when the GW passes Earth (rather than also each pulsar), we find constraints on the binary's total mass and GW frequency that are similar to a full signal analysis, yet ∼70 times more efficient.