2025/12/17 by Lange, Johannes U., Wells, Alexandra, Hearin, Andrew +76
#Cosmology and Nongalactic Astrophysics (astro-ph.CO) #FOS: Physical sciences
paper · doi:10.48550/arxiv.2512.15962
We present constraints on cosmic structure growth from the analysis of galaxy clustering and galaxy-galaxy lensing with galaxies from the Dark Energy Spectroscopic Instrument (DESI) Data Release 1. We analyze four samples drawn from the Bright Galaxy Survey (BGS) and the Luminous Red Galaxy (LRG) target classes. Projected galaxy clustering measurements from DESI are supplemented with lensing measurements from the Dark Energy Survey (DES), the Kilo-Degree Survey (KiDS), and the Hyper Suprime-Cam (HSC) survey around the same targets. Our method relies on a simulation-based modeling framework using the AbacusSummit simulations and a complex halo occupation distribution model that incorporates assembly bias. We analyze scales down to 0.4 h-1 Mpc for clustering and 2.5 h-1 Mpc for lensing, leading to stringent constraints on S8 = σ8 √(Ωm / 0.3) and Ωm when fixing other cosmological parameters to those preferred by the CMB. We find S8 = 0.794 ± 0.023 and Ωm = 0.295 ± 0.012 when using lensing measurements from DES and KiDS. Similarly, for HSC, we find S8 = 0.793 ± 0.017 and Ωm = 0.303 ± 0.010 when assuming the best-fit photometric redshift offset suggested by the HSC collaboration. Overall, our results are in good agreement with other results in the literature while continuing to highlight the constraining power of non-linear scales.