Unfinished fabric of the three neutrino paradigm
Francesco Capozzi, Eleonora Di Valentino, E. Lisi, A. Marrone, A. Melchiorri, A. Palazzo
Abstract
In the current 3ν paradigm, neutrino flavor oscillations probe three mixing angles (θ12,θ23,θ13), one CP-violating phase δ, and two independent differences between the squared masses mi2, that can be chosen as δm2=m22-m12>0 and Δm2=m32-(m12+m22)/2, where sign(Δm2)=+(-) for normal (inverted) mass ordering. Absolute ν masses can be probed by the effective mass mβ in beta decay, by the total mass ς in cosmology and - if neutrinos are Majorana - by another effective mass mββ in neutrinoless double beta decay. Within an updated global analysis of oscillation and nonoscillation data, we constrain these 3ν parameters, both separately and in selected pairs, and highlight the concordance or discordance among different constraints. Five oscillation parameters (δm2,|Δm2|,θ12,θ23,θ13) are consistently measured, with an overall accuracy ranging from ∼1% for |Δm2| to ∼6% for sin2θ23 (due to its persisting octant ambiguity). We find overall hints for normal ordering (at ∼2.5σ), as well as for θ23