Production & decay of a top quark and antiquark in the CDF detector at Fermi National Accelerator Laboratory (Fermilab) near Chicago. The computer image shows the detector in cross-section (blue). A proton and antiproton, accelerated in Fermilab's Tevatron collider, annihilate at centre to produce the top quark & antiquark. They live too briefly to be seen, but reveal themselves by their decays into jets of other particles (green) and two W particles. One W decays to a positron (magenta block, lower left) and an unseen neutrino (yellow arrow); the other W turns into two B mesons which decay to give the red tracks. The top quark was discovered at the CDF detector in 1992-3.