Potential higher radial excitations in the light pseudoscalar meson family

Inspired by the event accumulation around 2.6 GeV in the $\eta^\prime\pi^+\pi^-$ invariant mass spectrum of $J/\psi\to \gamma \eta^\prime\pi^+\pi^-$, which was reported by the BESIII Collaboration, we carry out the study of the mass spectrum and decay behavior of four radial excitations in the pseudoscalar meson family, which include $\eta^{(\prime)}(6S)$ and $\eta^{(\prime)}(7S)$. Combining with these analysis, we present the calculation of the reactions induced by a pion or kaon on the proton target which are relevant to these four discussed states. According to this information, we give concrete experimental suggestion of searching for them, which will become a new task for future experiments.
Comment: 10 pages and 12 figures