Too late to edit: I think the note [1] needs to be fixed. I think it's a cycle of quarks, down -> strange -> bottom -> down. https://en.wikipedia.org/wiki/Quark

Too late to edit: I think the note [1] needs to be fixed. I think it's a cycle of quarks, down -> strange -> bottom -> down. https://en.wikipedia.org/wiki/Quark#Weak_interaction https://en.wikipedia.org/wiki/Quark#Weak_interaction Anyway, before constructing a giant particle accelerator to measure that, better ask a particle physics expert :) .