Mapping the Galactic Center with Gravitational Wave Measurements using Pulsar Timing

Understand

We examine the nHz gravitational wave (GW) foreground of stars and black holes (BHs) orbiting SgrA* in the Galactic Center.

• A cusp of stars and BHs generates a continuous GW spectrum below 40 nHz; individual BHs within 1 mpc to SgrA* stick out in the spectrum at higher GW frequencies.
• The GWs and gravitational near-field effects can be resolved by timing pulsars within a few pc of this region.
• Observations with the Square Kilometer Array (SKA) may be especially sensitive to intermediate mass black holes (IMBHs) in this region, if present.