Project title: First Light with Euclid and JWST
Period: 1. 10. 2025-30. 9 .2027
Leading organization: University of Ljubljana, Faculty of Mathematics and Physics
Head: Maruša Bradač
Project description:
With the project First Light with Euclid and JWST (FLEW), we will develop a new generation of methods for reconstructing mass maps using gravitational lensing that will enable the full exploitation of the exceptional capabilities of the James Webb Space Telescope (JWST). Galaxy clusters act as powerful cosmic telescopes, magnifying the light from the faintest galaxies formed during the cosmic dawn. However, existing lensing models cannot keep up with the complexity of JWST data. The project builds upon the pioneering multi-parametric (gridded) approach to strong and weak lensing reconstruction (SWUnited) developed by the project leader. It will enable high-resolution maps of mass and magnification through advanced modelling and full MCMC sampling of an exceptionally large parameter space. The method will be developed in collaboration with ACEX Ltd., validated on six reference lensing galaxy clusters, and applied to a sample of 60 clusters observed in JWST Cycle 4 (the VENUS and CANUCS programs), complemented with HST data and extended to data from the Euclid mission. The project will deliver key scientific infrastructure for reliable, quantitative studies of the formation of the first galaxies, as well as for determining the timeline and driving mechanisms of cosmic reionization.
