Abstract
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In this talk, I will present a recent study on the measure of the flat-LCDM parameters using binary black hole coalescences observed by third-generation (3G) gravitational-wave detectors, like the Einstein Telescope (ET) and Cosmic Explorer (CE). Using simulated dark siren observations and a realistic simulated galaxy catalog, we combine gravitational-wave and galaxy data in a Bayesian framework to jointly estimate the Hubble constant H0 and the matter energy density parameter Om in different scenarios. Assuming a galaxy catalog complete up to z=1 and using dark sirens detected with a network signal-to-noise ratio greater than 300, we show that a network made of ET and two CEs can constrain H0 at a promising sub-percent level at 90% CI in one year of full observation. I will also discuss at what level we can constrain Om, how results change with different 3G network configurations, the importance of single-host dark sirens, and an optimistic scenario with a galaxy catalog complete up to z=3. Finally, I will discuss possible improvements to the analysis and future prospects.

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https://u-paris.zoom.us/j/89154692428?pwd=UFo5RVNvNFhEb2RSc1Fic3A0SzBBZz09

Meeting ID: 891 5469 2428
Passcode: 999118