Orateur
Description
Measuring the growth of cosmic structure across time is a powerful way to test the standard cosmological model. With the Euclid mission, we are gaining an unprecedentedly large and deep sample of Active Galactic Nuclei (AGN), providing a unique, highly biased tracer of large-scale structure reaching far into the high-redshift universe. In this work, we explore the cosmological potential of cross-correlating the spatial distribution of Euclid AGNs with Cosmic Microwave Background (CMB) lensing ($\kappa$) maps from different surveys (Planck, ACT, SO).
We first outline our forecasting framework based on the mock catalog from Euclid Preparation: XLIX (Bisigello et al., 2024), which presents a pure sample of millions of unobscured AGNs up to $z=5$. By modelling the $\kappa \times \text{AGN}$ cross-correlation, in combination with the auto-correlations $\kappa \times \kappa$ and $\text{AGN} \times \text{AGN}$, we forecast the constraining power of this joint analysis on the redshift evolution of structure growth $\sigma_8(z)$, linear AGN bias, and primordial non-Gaussianity $f_{\text{NL}}$ through the scale-dependent bias effect.
Following the measurement pipelines established in this theoretical work, the methodology is currently being adapted to the newly acquired Euclid Q1 data. We will discuss our ongoing progress and share early insights from this first look at real observations, outlining our steps toward measuring the clustering properties of the very first Euclid AGN sample.