IFIC Seminar: Cosmological neutrino mass bounds after DESI and their potential BSM implications

by Miguel Escudero (CERN)

Tuesday 1 Oct 2024, 12:00 → 13:00 Europe/Madrid

Primera-1-1-1 - Paterna. Seminario (IFIC)

On April 2024, the DESI collaboration combined their first year BAO results with CMB data to output a very stringent bound on the sum of neutrino masses: 0.073 eV at 95% CL and within the standard cosmological model. This value is very close to the lower bound inferred from neutrino oscillation experiments > 0.06 eV (normal ordering) > 0.10 eV (inverted ordering). In light of this, and based on 2407.13831, I will present a critical examination of this bound.

I will first review the main cosmological implications of neutrinos and then discuss the robustness of the cosmological neutrino mass bound by analyzing 1) the statistical procedure used to derive the bound, 2) potential statistical and systematic effects on the main cosmological data sets driving the bound, and 3) its robustness upon extensions of the cosmological model. I will discuss the main extensions of the Standard Model that could lead to relaxed cosmological bounds and highlight neutrino decays as a compelling possibility to reconcile stringent cosmological upper limits and data from the laboratory.
 

Escudero_IFIC_DESI_numass.pdf