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Regularities in electromagnetic decay widths

Alejandro Rivero
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Abstract

We revisit Sakurai's remark on the regularities of lepton-pair widths for mesons, extending the panorama to radiative $X \to γγ$ and total decays. The regularities persist, and somehow surprisingly some of them seem to relate with Fermi's constant -or $Z^0$-.

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Alejandro Rivero. 2006-03-20. Regularities in electromagnetic decay widths. https://arxiv.org/abs/hep-ph/0603145

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