- Seminars and Workshops
- Institute of Astronomy and Astrophysics
- Location
R1203 of the Astronomy-Mathematics Building, National Taiwan University
- Speaker Name
Chun-Hao To (Stanford University)
- State
Definitive
- Url
Three cosmic tracer fields are measured from imaging surveys: galaxy density, weak gravitation 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 the first part of the talk, I will present 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 describe the extensive validation of the measurements, modeling, and inferences using N-body simulations populated with galaxies. In the second part of the talk, I will 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 (DES-Y1). The talk will be concluded by a discussion on the implication of the result, potential improvements, and expected constraining powers in the up-coming DES-Y3 analysis and future wide imaging surveys. |