11:00 am–12:00 pm ERC 161
Title: Cosmology from a joint analysis of second and third order shear statistics
Abstract: Third-order shear statistics, e.g. three-point correlation function of shear or mass skewness, is one of the most natural extensions of the standard two-point correlation function, and one of the few cases that have an analytic expression in terms of the underlying power spectrum (in the perturbative regime) or bispectrum of large-scale structure. Because of its nice nature, 3pt has been studied for a long time, while its application to real data was limited until recently due to the challenges in the computational cost of measurement and theoretical prediction. In this talk, I will present the joint 2+3pt analyses applied to Dark Energy Survey and Hyper Suprime-Cam (Gomes+2025 [arxiv:2508.14018]; Sugiyama+2025 [arxiv: 2508.14019]) weak lensing data separately, utilizing a novel modeling pipeline of 3pt shear statistics based on multipole decomposition. I will also present a new data compression algorithm used in HSC analyses that suppresses the propagation of the noise in covariance to the final parameter inference, which is also useful for other general problems where the number of simulations is limited to infer a huge covariance matrix (Sugiyama and Park 2025 [arxiv:2508.14021]).
Zoom: https://uchicago.zoom.us/j/93802578500?pwd=NWNKLhJbCVfJkaam4yWCgRZXcntdhA.1
