Subthreshold poles in electron-positron annihilation. DD final states

Abstract: We show 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 make the fits to the BESIII data \cite{besiii2024} 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 subthreshold pole is greater than 4$\sigma$ in all cases.