From: Bob Cook * I would say that muons take less shielding than alphas of the same kinetic energy. The alphas are heavier, but also have more charge. Muons would be like a heavy electron losing kinetic energy by disrupting charged particles in a solid. Bob - That is why the shielding data is extremely disconcerting. They had expected that muon count rates would have slowed, but the last thing expected was for the count rate to actually increase in thick lead.
Given the short lifetime of the muons anyway, and the fact that the count rate should decrease both by natural decay and by absorption - this is doubly surprising. The short life of muons has never been challenged in any paper that I can find, and the logical conclusion of that is that we have to assume that whatever is happening to increase muons in the lead, is the result of one of the decay products. That is why the muon neutrino looks like the only choice – of the three decay products. Of course, there could be something completely unexpected happening.
