Nordita Astrophysics Seminars

Can baryonic feedback processes resolve the σ8 tension?

by Dr Sambit Giri (Nordita)

Albano 3:6228 - Mega (22 seats) (Albano Building 3)

Albano 3:6228 - Mega (22 seats)

Albano Building 3



Abstract: Weak lensing surveys favour a lower amplitude of the matter power spectrum, parameterised by σ8, compared to cosmic microwave background (CMB) observations. This discrepancy is known as the σ8 tension. In the past decade, it has become more and more evident that the energy injection of active galactic nuclei (AGN) has the potential to either heat up or push out large amounts of gas, altering the matter clustering signal at cosmological scales. This phenomenon is known as baryonic feedback process. The weak-lensing observations are sensitive to these baryonic feedback processes. Therefore modelling these processes carefully in our inference framework is crucial. In this talk, I will present a computationally cheap method to model the baryonic feedback processes and discuss its effects on the constraints put on the σ8 parameter.