Rare decay ${\pi }^0\to e^{+}{e}^{-}$ constraints on the light CP-odd Higgs in NMSSM

We constrain the light CP-odd Higgs $A_1^0$ in NMSSM via the rare decay ${\pi }^0\to e^{+}{e}^{-}$. It is shown that the possible $3\sigma$ discrepancy between theoretical predictions and the recent KTeV measurement of ${\cal B}({\pi}^{0}\to e^+ e^-)$cannotberesolvedwhentheconstraintsfrom$\Upsilon\to\gamma A_1^0$,$a_{\mu}$and$\pi^{0}\to \gamma \gamma$ are combined. Furthermore, the combined constraints also exclude the scenario involving $m_{A_1^0}=214.3$ MeV, which is invoked to explain the anomaly in the ${\mathrm{\Sigma }}^{+}\to p{\mu }^{+}{\mu }^{-}$ decay found by the HyperCP Collaboration.