Gravitational-wave dark siren cosmology systematics from galaxy weighting

The detection of GW170817 and its associated electromagnetic counterparts provided the first direct gravitational-wave measurement of the Hubble constant, H0, heralding the beginning of standard-siren cosmology. To date, there has only been a single gravitational-wave detection with an electromagnetic counterpart, but on the order of one hundred binary black hole detections without counterparts. These dark sirens can also be used for estimating cosmological parameters by considering all galaxies contained within the localization volume as potential hosts. Weighting the potential host galaxies by their luminosities (accounting for physically-motivated prescriptions such as tracing star formation or stellar mass) has the potential to improve the H0 measurement from the dark-siren method, but may also lead to biases. Using mock galaxy catalogs, we explore the potential biases in H0 inference from incorrectly weighted prescriptions.