Probing the large scale structure using gravitational-wave observations of binary black holes

Abstract

Third generation gravitational-wave (GW) detectors are expected to detect a large number of binary black holes (BBHs) to large redshifts, opening up an independent probe of the large scale structure using their clustering. This probe will be complementary to the probes using galaxy clustering - GW events could be observed up to very large redshifts (z∼10) although the source localization will be much poorer at large distances (∼tens of square degrees). We explore the possibility of probing the large scale structure from the spatial distribution of the observed BBH population, using their two-point (auto)correlation function. We find that we can estimate the bias factor of the population of BBHs (up to z∼0.7) with a few years of observations with these detectors. Our method relies solely on the source-location posteriors obtained from the GW events and does not require any information from electromagnetic observations. This will help in identifying the types of galaxies that host the BBH population, thus shedding light on their origins.