Probing cosmic chemical enrichment with next-generation gravitational-wave observatories

Understand

By observing binary black hole (BBH) mergers out to the edge of the Universe, next-generation (XG) ground-based gravitational-wave (GW) detectors like Cosmic Explorer and Einstein Telescope will map the BBH merger rate across all of cosmic history.

• This merger rate traces the formation rate of their progenitor stars convolved with a delay time distribution.
• Given theoretically-motivated priors on the delay time distribution, we show how XG observations can measure the BBH progenitor formation rate, probing the star formation rate (SFR) up to $z > 15$.
• However, the progenitor formation rate does not directly give a measurement of the SFR, but rather a combination of the SFR and its metallicity distribution as a function of redshift.