Historical Content Note: The following material is reprinted from publications from throughout Fermilab's history. It should be read in its original historical context.

How do scientists learn about the elusive neutrino?

How do scientists learn about the elusive neutrino? This is a composite photograph showing one of the events found in the Fermilab 15-ft. Bubble Chamber during a run in which the Chamber was filled with neon and hydrogen, exposed to a beam of neutrinos, and recorded by Experiment #28A. A neutrino interaction is indicated at the vertex of the event.

View 1 above is a photograph of the entire event. View 2 is a close-up of the vertex of the event shown in the rectangle outlined in View 1. View 3 is a schematic explanation of the event.

These events are interpreted by the experimenters as involving the production of a new particle in the neutrino interaction, a particle which then decays into a neutral K meson, a positron and an invisible neutrino. The original neutrino turns into a muon.