Precise predictions
Over 20 million Z0 bosons have been produced in electronpositron collisions at the LEP and SLC accelerators, making it one of the most studied particles in high-energy physics. The number of Z0 bosons produced as a function of centre-of-mass energy is sensitive to the number of types of neutrino. Early measurements at the LEP experiments (black points) confirmed that there are precisely three types of neutrino.