Weak Lensing Non-Gaussian Statistics in the era of precision Cosmology

by Marco Gatti (Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, PA 19104, USA)

Aula Conversi (Dip. di Fisica - Edificio G. Marconi)

Aula Conversi

Dip. di Fisica - Edificio G. Marconi


The statistical analysis of lensed galaxies is a powerful tool to study the dark matter distribution of the Universe. For instance, the distortion of galaxy shapes induced by the large-scale structure of the Universe can be used to reconstruct the projected matter density along the line-of-sight (mass maps). Mass maps are useful as they provide a wealth of information that goes beyond and complements the more traditional two-point statistics used in Cosmology. During this seminar, I will show the Dark Energy Survey year 3 mass maps, which are the largest curved-sky galaxy weak lensing mass maps to date. Next, I will discuss the current state-of-the-art in non-Gaussian analyses applied to weak lensing mass maps. I will present an end-to-end simulation-based inference (SBI) framework that allows us to use common non-Gaussian statistics (e.g., higher order moments, peaks, scattering transform, phase wavelet harmonics) to constraints cosmological parameters. I will then show constraints on data using the Dark Energy Survey year 3 weak lensing data. Last, I will be discussing the impact of observational systematics, and the main challenges ahead in view of stage IV surveys.

Organized by

R. Maoli