Baryon-free $S_8$ tension with Stage IV cosmic shear surveys

Understand

Accurately modelling matter power spectrum effects at small scales, such as baryonic feedback, is essential to avoid significant bias in the estimation of cosmological parameters with cosmic shear.

• However, Stage IV surveys like LSST will be so precise that significant information can still be extracted from large scales alone.
• In this work, we simulate LSST Y1-like mock data and perform a cosmic shear analysis, considering different models of baryonic feedback.
• To focus on large scales, we apply physically motivated scale cuts which account for the redshift dependence of the multipoles in the tomographic bin.