Speaker
Description
We review recent advancements in the measurement of the weak gravitational lensing (WL) signature induced by the potentials of galaxy clusters onto the shapes of background galaxies. In the context of wide photometric surveys, we discuss how this poses unique challenges and opportunities and how we addressed and leveraged them. After discussing the recent advancements in the measurement of WL, focussing on the work done in the Dark Energy Survey, the Kilo Degree Survey, and the Hyper Supreme Camera Strategic Survey Program for eROSITA selected clusters, we elaborate on the theoretical modeling necessary to interpret the measured WL signal. We base our discussion on the synthetic shear profile simulations proposed in SG+21, which allow us to calibrate the WL bias and WL scatter and their systematic uncertainties, as well as its recent application in the WL mass calibration of the eROSITA cluster number counts (SG+24a). These calibrations and the WL data enable accurate and precise cluster number count experiments. In this context, we will focus on the different uses of WL data by cosmic shear, galaxy correlation studies, and cluster number counts to highlight these large-scale structure probes' joint systematics and physical complementarity. Based on a pilot study, SG+24b, we outline how WL by galaxy clusters can help better understand the impact of baryon feedback effects on the matter power spectrum at small scales. We conclude our presentation with an outlook to the newly started Euclid mission and how it will impact cluster WL.
