${{\mathit K}_L^0}$ $\rightarrow$ ${{\mathit \mu}^{+}}{{\mathit \mu}^{-}}$   Decay Mode Summary INSPIRE   PDGID:
S013.6
Mode (*) Fraction ($\Gamma_i$ / $\Gamma$) Scale Factor/
Conf. Level		 P(MeV/c)  
$\Gamma_{23}$ ${{\mathit K}_L^0}$ $\rightarrow$ ${{\mathit \mu}^{+}}{{\mathit \mu}^{-}}$ ($6.84$ $\pm0.11$) $ \times 10^{-9}$ 225
Category: Charge conjugation ${\times }$ Parity ($\mathit CP$) or Lepton Family number ($\mathit LF$) violating modes, or $\Delta \mathit S$ = 1 weak neutral current ($\mathit S1$) modes
Note: (S1) Allowed by higher-order electroweak interactions.
The following data is related to the above value:
$\Gamma($ ${{\mathit K}_L^0}$ $\rightarrow$ ${{\mathit \mu}^{+}}{{\mathit \mu}^{-}}$ $)/\Gamma($ ${{\mathit K}_L^0}$ $\rightarrow$ ${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}$ $)$
$\Gamma_{23}/\Gamma_{8}$