Hunting for the host galaxy groups of binary black holes and the application in constraining Hubble constant

Understand

The discovery of gravitational-wave (GW) signals, produced by the coalescence of stellar-mass binary black holes (SBBHs), opens a new window to study the astrophysical origins and dynamical evolutions of compact binaries.

• In addition, these GW events can be treated as the standard sirens to constrain various cosmological parameters.
• Both issues require the host identification for these GW events, with help of the spatial resolution of GW detector networks.
• In this paper, we investigate the capabilities of various detector networks for identifying the SBBHs' host galaxy groups, rather than their host galaxies, which can overcome the influence of galaxies' proper motions in dark matter halos for measuring the cosmological parameters.