Quantifying baryon effects on the matter power spectrum and the weak lensing shear correlation

Understand

Feedback processes from baryons are expected to strongly affect weak-lensing observables of current and future cosmological surveys.

• In this paper we present a new parametrisation of halo profiles based on gas, stellar, and dark matter density components.
• This parametrisation is used to modify outputs of gravity-only $N$-body simulations (following the prescription of Schneider and Teyssier [1]) in order to mimic baryonic effects on the matter density field.
• The resulting baryonic correction model relies on a few well motivated physical parameters and is able to reproduce the redshift zero clustering signal of hydrodynamical simulations at two percent accuracy below $k\sim10$ h/Mpc.