Inquiring Minds

DONUT Details: The Signal of a Tau Neutrino

Scientists can detect a tau neutrino only by identifying its interaction with an atomic nucleus. This process creates a tau lepton, whose track can be recorded using emulsion, a kind of three-dimensional "photographic film." The main signature of a tau lepton is a one-millimeter-long track ending in a kink, indicating the decay of the tau lepton. The graphic below shows the particle tracks of a tau neutrino event recorded by the DONUT collaboration.

View diagram