Search for the Decayη→π0+e++e−

Abstract

A search has been made for the decay $\eta \to {\pi }^0+e^{+}+e^{-}$, which should be very rare if $C$ is conserved in strong and electromagnetic interactions. We have found no events consistent with this decay in a sample of $\eta$ produced in the reaction $K^{-}+p\to \Lambda +\eta$. The upper limit for this decay, at the 90% confidence level, is $R=\frac{(\eta \to {\pi }^0+e^{+}+e^{-})}{(\eta \to \gamma +\gamma )}<0.047\mathrm{}$.