Events in Delphi

In this event we see two single tracks moving away from the central collision region, depositing some energy in the outer detectors, but almost none in the electron-photon layer (the bright orange ring). These tracks are due to a muon and an antimuon. Muons are heavy versions of electrons, and penetrate matter more easily. They are common in cosmic rays (naturally occurring particles that rain down through the atmosphere) at ground level.

c.sutton 26/9/97