18–20 mai 2026
Fuseau horaire Europe/Paris

Breaking Through Blending : A Multi-Survey Approach to Dark Energy with LSST, Euclid, and Roman

20 mai 2026, 09:40
20m

Orateur

Samuel Mesquita (IN2P3/LPSC)

Description

Surveys like the Vera C. Rubin Observatory's LSST, ESA's Euclid, and NASA's Roman Space Telescope aim to explore dark energy through measurements of weak gravitational lensing and large-scale structure. However, blending, where faint overlapping galaxy sources are misidentified, introduces substantial errors in galaxy shape and flux measurements, especially for deep, ground-based surveys like LSST. This effect poses a major challenge to accurate WL measurements.

In this talk, I will present my first results when characterizing blending in LSST commissioning (Data Preview 1) and show the importance of a new metric developped in the context of Manon Ramel's PhD, the blending entropy, for these analyses. I will then talk about my other project which aims to quantify the impact of blending on the 3x2pt cosmological analysis using CosmoDC2.

PhD Advisor : Cyrille Doux

Auteurs

Dr Cyrille Doux (IN2P3/LPSC) Samuel Mesquita (IN2P3/LPSC)

Documents de présentation