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New upper limit on the decay<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mi>η</mml:mi><mml:mo>→</mml:mo><mml:mrow><mml:msup><mml:mrow><mml:mi>e</mml:mi></mml:mrow><mml:mrow><mml:mo>+</mml:mo></mml:mrow></mml:msup></mml:mrow><mml:mrow><mml:msup><mml:mrow><mml:mi>e</mml:mi></mml:mrow><mml:mrow><mml:mi>−</mml:mi></mml:mrow></mml:msup></mml:mrow></mml:math>
We have searched for the rare decay of the $\ensuremath{\eta}$ meson $\ensuremath{\eta}\ensuremath{\rightarrow}{e}^{+}{e}^{\ensuremath{-}}$ using the CLEO II detector. The $\ensuremath{\eta}$'s were produced in ${e}^{+}{e}^{\ensuremath{-}}$ collisions with 10 GeV center-of-mass energy at the Cornell Electron Storage Ring (CESR). We find with $90%$ confidence the upper limit on the branching fraction $B(\ensuremath{\eta}\ensuremath{\rightarrow}{e}^{+}{e}^{\ensuremath{-}})<7.7\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}5}$. The …