Open Group Seminar: Chun-Hao To (Stanford University)

1:30–2:30 pm Zoom Room (online)

Chun-Hao To, Stanford University, "Cosmological constraints from a joint analysis of cluster abundances, galaxy correlations, and weak gravitational lensing in the Dark Energy Survey"

Three cosmic tracer fields are measured from imaging surveys: galaxy density, weak gravitational lensing shear, and cluster density. The joint analysis of the auto and cross correlations of the first two fields, often referred to as the 3x2pt analysis, has become a popular and competitive cosmological test of the standard cosmological model. The abundances and spatial distributions of galaxy clusters, which are associated with the highest peaks in the matter density field, provide another powerful probe of cosmic structure formation and evolution; thus, the combination of cluster abundances and 3x2pt analysis is expected to yield precise cosmological constraints. In this talk, I will describe a novel multi-probe cluster cosmology analysis, which focuses exclusively on large scales. This new cluster cosmology analysis yields competitive cosmological constraints while being robust against several systematics. I will then present cosmological constraints from the first joint analysis of cluster abundances and auto/cross correlations of all three cosmic tracer fields measured from the first year of the Dark Energy Survey (DESY1). The talk will be concluded by a discussion on the implication of the result, potential improvements, and expected constraining powers in the up-coming DESY3 analysis and future wide imaging surveys.

Event Type


Nov 5