Orateur
Description
Galaxy clusters are among the most powerful probes of cosmology, providing key insights into the growth of structure and the nature of dark energy. However, translating cluster observations into robust cosmological constraints remains challenging, primarily due to uncertainties in mass calibration and systematic effects. Upcoming surveys such as the Rubin Observatory’s LSST and Euclid will deliver samples of hundreds of thousands of optically selected clusters, requiring new data analysis approaches to fully exploit their potential.
In this talk, we introduce capish, a new simulation-based inference framework for optical cluster cosmology. capish forward-models cluster abundances and lensing masses while naturally incorporating essential systematics — including correlated scatter between cluster richness and cluster lensing mass, selection effects, and super-sample variance of has number counts — without relying on simplified analytic likelihoods.
