I will provide an overview of the recent final data release of the ESO Kilo-Degree Survey and the associated cosmology results using weak gravitational lensing. As the field transitions to the next generation of surveys with Euclid and Rubin, I will discuss the current state of analysis choices, calibration and validation, and some lessons learnt.
Tidal field can cause distortion of galaxy shape and leaves characteristic imprint on the galaxy density-shear correlation on the BAO scale. This is the so-called GI BAO. It bridges the gap between BAO and shear measurement, and serves as a useful consistency check. Using the DES data, we report the first measurement of the GI BAO using photometric data alone. Despite the low detection...
Recent 2σ–4σ deviations from the cosmological constant $\Lambda$ suggest that dark energy (DE) may be dynamical, based on baryon acoustic oscillations and full-shape galaxy clustering analyses. This calls for even tighter DE constraints to narrow down its true nature. In this talk, I present how galaxy intrinsic alignments (IA) can enhance the full-shape galaxy clustering–based DE constraints,...
As underdense regions in the universe, cosmic voids are less affected by non-linear gravitational evolution and baryonic feedback, providing a clean environment for constraining cosmological parameters. In particular, the void density profile is sensitive to cosmology, but remains challenging to measure in observations. In this work, we investigate the method to constrain the void density...
Cosmic shear surveys serve as a powerful tool for mapping the underlying matter density field, including non-visible dark matter. A key challenge in cosmic shear surveys is the accurate reconstruction of lensing convergence (κ) maps from shear catalogs impacted by survey boundaries and masks, which seminal Kaiser-Squires (KS) method are not designed to handle. To overcome these limitations, we...
