Neutrino Oscillation & Dark Matter Halo Simulator

Neutrinos are born in a single flavor but are actually a superposition of three mass eigenstates travelling at slightly different phases, so the flavor composition of a beam oscillates with distance — the same physics behind the solar neutrino problem and the MSW resonance. This simulator renders that beam directly: thousands of particles stream from a source toward a detector, each colored moment-to-moment by the two-flavor survival probability P(νe→νe) = 1 − sin²(2θ)·sin²(1.267·Δm²·L/E) at its current position, so the oscillation pattern appears as moving bands of color along the beam. Around it drifts a translucent cloud standing in for a galaxy's dark-matter halo, the unseen mass inferred from flat rotation curves. Tune the baseline distance, neutrino energy, mass-squared splitting Δm² and mixing angle θ to see how each reshapes the oscillation wavelength and the flavor mix arriving at the detector.