PhD student Gabriele Perna, now a Postdoc,

Our research explores how future gravitational wave (GW) observations—especially those without electromagnetic counterparts—can still be used to infer key cosmological parameters like the Hubble constant (H₀). We investigate how incorrect assumptions about the GW host galaxy distribution, particularly regarding luminosity and redshift, can bias H₀ measurements. Using realistic galaxy and compact binary coalescence simulations, we show that such biases depend on both the observational footprint and distance of GW events. Our findings emphasise the need for accurate modelling of host probabilities when combining GW data with galaxy catalogues.

Please, feel free to read our paper and reach out to us for any question or suggestion.

Figure: Hubble constant posterior calculated using 200 well-localised dark sirens when assuming different models for the galaxies’ hosting probability of binary black holes. The true underlying astrophysical population is generated with the model indicated on the top left panel.