📝 SummarXiv

Abstract

We prove that the ${\psi(2\mathrm S)}$ subthreshold pole influences the cross section of the electron-positron annihilation into the ${\mathrm D\bar\mathrm D}$ final states. We perform fits to the merged BES \cite{bes2008} and BESIII \cite{besiii2024} data on ${\mathrm D^0\bar\mathrm D^0}$ and ${\mathrm D^+\mathrm D^-}$ final states, and also two common fits to both processes. The statistical significance of the ${\psi(2\mathrm S)}$ subthreshold pole in all these fits reaches values greater than 6.5$\sigma$.