Speaker
Description
One of Euclid's key projects will be the so-called 3x2pt analysis, i.e., the combination of cosmic shear, photometric galaxy clustering, and galaxy-galaxy lensing (the cross-correlation of lens galaxy positions with the shapes of source galaxies). While Euclid has set quality requirements for the photometric redshift (photo-z) precision needed for the sources (used to measure cosmic shear), there are no requirements set for the photo-z precision of the lenses (used to measure photometric galaxy clustering). Moreover, previous work from the Dark Energy Survey indicates that the width of the lens redshift distributions (besides the mean) can have a significant impact on the resulting constraints. I will briefly present some preliminary tests on the impact of these uncertainties on the cosmological constraints from Euclid DR1 photometric galaxy clustering.
