We present cross sections for $e^{+}{e}^{-}\to \mathrm{hadrons}$, $e^{+}{e}^{-}$, and ${\mu }^{+}{\mu }^{-}$ near 3095 MeV. The $\psi \mathrm{}\left(3095\right)\mathrm{}$ resonance is established as having an assignment $J^{\mathrm{PC}}=1^{--}$. The mass is 3095 ±4 MeV. The partial width to electrons is ${\Gamma }_e=4.8\mathrm{}\pm 0.6$ keV and the total width $\Gamma =69\mathrm{}\pm 15$ keV. Total rates and interference measurements for the lepton channels are in accord with $\mu -e$ universality.

• Received 7 April 1975

DOI:https://doi.org/10.1103/PhysRevLett.34.1357