Euclid: The importance of galaxy clustering and weak lensing cross-correlations within the photometric Euclid survey

Understand

The data from the Euclid mission will enable the measurement of the photometric redshifts, angular positions, and weak lensing shapes for over a billion galaxies.

• This large dataset will allow for cosmological analyses using the angular clustering of galaxies and cosmic shear.
• The cross-correlation (XC) between these probes can tighten constraints and it is therefore important to quantify their impact for Euclid.
• In this study we carefully quantify the impact of XC not only on the final parameter constraints for different cosmological models, but also on the nuisance parameters.