Keywords: K0 decay to muons.svg en Decay of the K<sup>0</sup> meson to a muon pair The two Feynman diagrams with an intermediate up quark and a charm quark contribute with opposite signs and therefore cancel each other almost completely making the overall branching ratio very small This cancellation is called the GIM mechanism 2016-07-10 own Blibla other versions cc-zero Feynman diagrams |