Gravitational-wave dark siren cosmology systematics from galaxy weighting

Understand

The detection of GW170817 and the measurement of its redshift from the associated electromagnetic counterpart provided the first gravitational wave determination of the Hubble constant ($H_0$), demonstrating the potential power of standard-siren cosmology.

• In contrast to this bright siren approach, the dark siren approach can be utilized for gravitational-wave sources in the absence of an electromagnetic counterpart: one considers all galaxies contained within the localization volume as potential hosts.
• When statistically averaging over the potential host galaxies, weighting them by physically-motivated properties (e.g., tracing star formation or stellar mass) could improve convergence.
• Using mock galaxy catalogs, we explore the impact of these weightings on the measurement of $H_0$.