The Rare Decays $\piee$, $\etaee$ and \etamumu$ in Chiral Perturbation Theory
arXiv:hep-ph/9207233 · doi:10.1016/0370-2693(92)91407-Z
Abstract
We calculate the decay rates for $\piee$, $\etaee$ and $\etamumu$ in chiral perturbation theory. The linear combination of counterterms necessary to render these amplitudes finite is fixed by the recently measured branching fraction for $\etamumu$. We find $\Br(\piee ) = 7\pm 1\times 10^{-8}$ and $\Br(\etaee )=5\pm 1\times 10^{-9}$.
(6 pages, 1 figure available on request, uses harvmac.tex), UCSD/PTH 92-23, CALT-68-1803