Slow Muon Physics
Recently, slow positive muons (μ+) have been observed to be emitted from solid rare-gas moderators exposed to a 4.2 MeV incident μ+ beam. Energy spectra obtained from the time of flight data indicate a maximum at ∿ 5 eV with a tail extending to higher energies. The data suggest a “hot muon” emission mechanism, implying a long diffusion length for low-energy μ+ in these solids. Of the targets measured, argon was observed to produce the highest yield (∿ 10−5slow μ+ per incident μ+), providing a useful flux for further experimentation. The discussion presented here centers around these results and their future implications for slow μ+, Mu (μ+e−) and Mu− (μ+e−e−) beams. The applications of such beams will also be discussed.
KeywordsHelium Atom Positive Muon Solid Argon Charge Exchange Cross Section Muonic Helium
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