Animated particle tracks of the production and decay of a charmed sigma particle. The sigma (containing a charm quark) lives too briefly to be seen, but is inferred from other particles. A neutrino enters unseen from top left, and collides with a proton in the bubble chamber liquid, producing a negative muon (red) and the sigma. The sigma decays to one negative pion (green, top), three positive pions (blue), and an unseen neutral lambda which betrays itself when it decays to a proton (purple) and a negative pion (green, bottom). The muon and one of the pions knock out atomic electrons which produce the two spiral tracks (yellow).