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arXiv · hep-ph/9405230

Atomic Alchemy

C. Greub·D. Wyler·S. Brodsky·C. Munger
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Abstract

We consider the transitions between electromagnetic bound states, such as the exclusive weak decay of a muonic atom into an electronic atom: $(μ^- Z) \to (e^- Z) {\bar ν_e }ν_μ. $ We show that relativistic effects in the atomic wavefunctions are crucial for determining the rate. In the case of heavy atoms, the exclusive channel branching ratios exceed $10^{-6},$ possibly bringing the study of these rare decays within experimental reach. Such processes thus provide a detailed laboratory for studying the high momentum tail of wavefunctions in atomic physics; in addition, they provide a simple toy model for investigating analogous exclusive heavy hadronic decays in quantum chromodynamics such as $B \to πe ν.$

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C. Greub, D. Wyler, S. Brodsky, C. Munger. 1994-05-05. Atomic Alchemy. https://doi.org/10.1103/physrevd.52.4028

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