Semi-Analytic Galaxy Formation in Massive Neutrino Cosmologies

Understand

The constraints on neutrino masses led to the revision of their cosmological role, since the existence of a cosmological neutrino background is a clear prediction of the standard cosmological model.

• In this paper, we study the impact of such background on the spatial distribution of both Dark Matter (DM) and galaxies, by coupling $N$-body numerical simulations with semi-analytic models (SAMs) of galaxy formation.
• Cosmological simulations including massive neutrinos predict a slower evolution of DM perturbations with respect to the $\Lambda$CDM runs with the same initial conditions and a suppression on the matter power spectrum on small and intermediate scales, thus impacting on the predicted properties of galaxy populations.
• We explicitly show that most of these deviations are driven by the different $\sigma_8$ predicted for cosmologies including a massive neutrino background.