Photo-z outlier self-calibration in weak lensing surveys

Understand

Calibrating photometric redshift errors in weak lensing surveys with external data is extremely challenging.

• We show that both Gaussian and outlier photo-z parameters can be self-calibrated from the data alone.
• This comes at no cost for the neutrino masses, curvature and dark energy equation of state $w_0$, but with a 65% degradation when both $w_0$ and $w_a$ are varied.
• We perform a realistic forecast for the Vera Rubin Observatory (VRO) Legacy Survey of Space and Time (LSST) 3x2 analysis, combining cosmic shear, projected galaxy clustering and galaxy - galaxy lensing.