Speaker
Description
We explore the tomographic angular cross-correlation between gravitational-wave and galaxy catalogs as a probe of late-time cosmology. Focusing on next-generation interferometers combined with the Euclid photometric survey, we forecast constraints on the Hubble constant, Matter density parameter and other cosmological parameters.
Our analysis accounts for realistic GW populations, observational uncertainties, and nuisance parameters. This method can constrain the Hubble constant to percent-level accuracy, even when marginalizing over biases and other cosmological parameters. Combining galaxy auto-correlation with GW–galaxy cross-correlation boosts sensitivity by up to a factor of $\sim10$ compared to either probe alone.
We also discuss the use of a spectroscopic redshift catalog, as well as the detectability of the clustering bias of gravitational--wave sources.