Forecast of cosmological parameters from 1D M_ap in a 100 deg² survey at Euclid depth. Marginalized 2D (1 and 2σ contours) and 1D (full likelihood) constraints are displayed in blue without tomography and in green for a tomographic analysis with 5 redshift slices and including auto- and cross-M_ap terms between redshift slices. Dashed lines correspond to the 1σ constraints in the 1D marginalized likelihood. The red crosses and lines indicate the input values while the blue and green crosses indicate the best estimate in the 2D constraints. Gray crosses correspond to parameters of the 25 cosmo-SLICS simulations that are used to estimate the cosmology dependence of 1D M_ap.