ψ(3684)Radiative Decays to High-Mass States

Abstract

We present experimental evidence for the existence of the decay $\psi \mathrm{}\left(3684\right)\mathrm{}\to \gamma \chi$, $\chi \to 4{\pi }^{\pm }, 6{\pi }^{\pm }, {\pi }^{+}{\pi }^{-}{K}^{+}{K}^{-}, {\pi }^{+}{\pi }^{-}, \mathrm{and} K^{+}{K}^{-}$. There is clear evidence for at least two $\chi$ states, one at 3.41 ± 0.01 GeV/${\mathit{c}}^2$ and the other at 3.53±0.02 GeV/${\mathit{c}}^2$. The $\chi \mathrm{}\left(3410\right)\mathrm{}$ decays into $\pi \pi$ and $\mathrm{KK}$ and thus must have even spin and parity.