Modeling neutral hydrogen (HI) at the field level

by Andrej Obuljen (University of Zurich)

Wednesday 16 Nov 2022, 11:30 → 13:30 Europe/Zurich

4/2-011 - TH common room (CERN)

I will present results from our recent work on modeling neutral hydrogen (HI) at the field level (https://arxiv.org/abs/2207.12398). We use an analytical forward model based on perturbation theory to predict HI overdensity maps at low redshifts. We investigate its performance by comparing it directly at the field level to the simulated HI from the IllustrisTNG magneto-hydrodynamical simulation TNG300-1, in both real and redshift space. I will show results on the overall performance in terms of scales at which this approach accurately captures the simulated HI field and discuss the inferred HI noise properties. Finally, I will provide a simple prescription based on the perturbative forward model which can be used to efficiently generate accurate HI mock data, in real and redshift space.