This Day in Science History
Physicists Find First Direct Evidence For Tau Neutrino
July 21, 2000 — Scientists have announced at Fermi National Accelerator Laboratory that they have produced the first direct evidence of the tau neutrino, confirming the existence of an extraordinarily elusive constituent of matter.
Earlier experiments had produced only indirect evidence for the existence of the tau neutrino, which is massless or almost massless, carries no electric charge and barely interacts with surrounding matter.
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