Neutrino Flavor Oscillations & PMNS Matrix

Neutrinos are produced as flavor eigenstates (ν_e, ν_μ, ν_τ) but propagate as mass eigenstates. The PMNS mixing matrix (Pontecorvo–Maki–Nakagawa–Sakata) rotates between bases, causing quantum interference that periodically changes the observed flavor.

P(ν_e)

P(ν_μ)

P(ν_τ)

θ₁₂ (solar, °) 33.5°

θ₂₃ (atm, °) 45.0°

θ₁₃ (reactor, °) 8.5°

δCP (°) 0°

Δm²₂₁ (×10⁻⁵ eV²) 7.4

Energy (MeV) 10 MeV