Pair-Production of W Particles
An electron-positron collison seems to have produced
a pair of W particles. Observed by the OPAL experiment
in July, 1996.
Both W particles decayed into a pair of quarks, which then
became a narrow bundle of out-going particles (called a "jet"),
resulting in 4 jets of particles (making a cross in this picture).
hisho@icepp.s.u-tokyo.ac.jp