Figure 1
APS/Alan Stonebraker

Figure 1: A Feynman diagram represents the decay of a neutral B-meson, Bs0, to a pair of muons, μ+μ-. The green sphere on the left indicates the meson, which is a bound state of a strange quark and an antibottom quark. These radiate two W bosons and exchange a top quark in the process. The W bosons fuse to a Z boson, which then produces the two muons in the final state.