The $\psi$(2S) state as a subthreshold pole in electron positron annihilation into $D\bar{D}$ final states

Abstract

By performing a fit to the merged BES 2008 and BESIII 2024 $e^{+}{e}^{-}\to D\bar{D}$ cross-section data, we find that the $\psi (2\mathrm{S})$ subthreshold pole influences this process markedly. The statistical significance of the $\psi (2\mathrm{S})$ as a subthreshold pole is 8$\sigma$. A fit assuming it and seven resonances excels with the fit quality characterized by ${\chi }^2/\mathrm{DOF}=240.4/284$, which means a $p$-value of 97\%. The interference of resonances with the continuum provided by the subthreshold pole changes their shapes, positions, and widths.

7 pages, 6 figures

References in corpus (1)

• Physics of the Analytic S-Matrix