Lifting weak lensing degeneracies with a field-based likelihood

by Dr Natalia Porqueres (Oxford)

Thursday 13 Jun 2024, 11:00 → 12:00 Europe/Stockholm

FA32 (AlbaNova Main Building)

With Euclid and the Vera Rubin Observatory starting their observations, we need highly precise and accurate data analysis techniques to optimally extract the information from weak lensing data. However, the standard approach of fitting some summary statistics is inevitably suboptimal and imposes approximations on the statistical and physical modelling. I will present a new method for weak lensing analysis based on a full physics model and field-based statistics. By analysing the data at the pixel level, this method lifts the weak lensing degeneracy and provides uncertainties on the cosmological parameters up to a factor 5 smaller than those from standard techniques on the same data. I will discuss the current status and ways to meet the challenges of this approach for its first real data application.