6533b834fe1ef96bd129d52c

RESEARCH PRODUCT

Simultaneous description of the e+e−→J/ψππ(KK¯) processes

subject

description

In this work, we provide a simultaneous and accurate description of the ${\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}$ and ${\ensuremath{\pi}}^{\ifmmode\pm\else\textpm\fi{}}J/\ensuremath{\psi}$ invariant mass distributions of the recent BESIII data on ${e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}J/\ensuremath{\psi}{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}$, together with the ${e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}J/\ensuremath{\psi}{K}^{+}{K}^{\ensuremath{-}}$ cross sections at ${e}^{+}{e}^{\ensuremath{-}}$ center-of-mass energies $q=4.23\text{ }\text{ }\mathrm{GeV}$ and $q=4.26\text{ }\text{ }\mathrm{GeV}$. The rescattering effects between pions in the S and D waves are taken into account through the Muskhelishvili-Omn\`es formalism. Since the physical region of the $\ensuremath{\pi}\ensuremath{\pi}$ invariant mass extends above 1 GeV, the important $K\overline{K}$ intermediate state in the S wave is implemented through coupled-channel unitarity. For the left-hand cuts, we account for the well established charged exotic state ${Z}_{c}(3900)$ in $t$ and $u$ channels, while the other contributions are absorbed in the subtraction constants. For the ${e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}J/\ensuremath{\psi}K\overline{K}$, we provide the prediction of the two-kaon invariant mass distribution. The constructed amplitudes serve as an essential framework to interpret the present and forthcoming measurements by the BESIII and Belle II Collaborations.