Identification of a Pseudoscalar State at 1440 MeV inJψRadiative Decays

From a partial-wave analysis of the $K\overline{K}\pi$ system in the decay $\frac{J}{\psi }\to \gamma K^{+}{K}^{-}{\pi }^0$, it is determined that the quantum numbers of the $K\overline{K}\pi$ resonance at 1440 MeV, previously identified as the $E\left(1420\right)\mathrm{}$, are $J^{\mathrm{PC}}=0^{-+}$. This new particle has been named the $\iota$.