Effective-Lagrangian study of ${\psi }^{\prime }(J/\psi )\to VP$ and the insights into $\rho \pi$ puzzle

Abstract

Within the effective Lagrangian approach, we carry out a unified study of the $J/\psi ({\psi }^{\prime })\to VP$, $J/\psi \to P\gamma$ and relevant radiative decays of light-flavor hadrons. Large amount of experimental data, including the various decay widths and electromagnetic form factors, are fitted to constrain the numerous hadron couplings. Relative strengths between the strong and electromagnetic interactions are revealed in the $J/\psi \to VP$ and ${\psi }^{\prime }\to VP$ processes. The effect from the strong interaction is found to dominate in the $J/\psi \to \rho \pi$ decay, while the electromagnetic interaction turns out to be the dominant effect in ${\psi }^{\prime }\to \rho \pi$ decay, which provides an explanation to the $\rho \pi$ puzzle. For the $J/\psi \to K^{\ast }\bar{K}+{\bar{K}}^{\ast }K$ and ${\psi }^{\prime }\to K^{\ast }\bar{K}+{\bar{K}}^{\ast }K$, the former process is dominated by the strong interactions, and the effects from the electromagnetic parts are found to be comparable with those of strong interactions in the latter process. Different $SU(3)$ breaking effects from the electromagnetic parts appear in the charged and neutral channels for the ${\psi }^{\prime }\to K^{\ast }\bar{K}+{\bar{K}}^{\ast }K$ processes explain the rather different ratios between $B({\psi }^{\prime }\to K^{\ast +}{K}^{-}+K^{\ast -}{K}^{+})/B(J/\psi \to K^{\ast +}{K}^{-}+K^{\ast -}{K}^{+})$ and $B({\psi }^{\prime }\to K^{\ast 0}{\bar{K}}^0+{\bar{K}}^{\ast 0}{K}^0)/B(J/\psi \to K^{\ast 0}{\bar{K}}^0+{\bar{K}}^{\ast 0}{K}^0)$.

20 pages, 5 figures

References in corpus (7)

• Towards a consistent estimate of the chiral low-energy constants
• Study of the electromagnetic transition form-factors in η-> μ^+μ^-γand ω-> μ^+μ^-π^0 decays with NA60
• Exotic and excited-state radiative transitions in charmonium from lattice QCD
• One meson radiative tau decays
• Unified study of $J/\psi \to PV$, $P{\gamma }^{(\ast )}$ and light hadron radiative processes
• Understanding the radiative decays of vector charmonia to light pseudoscalar mesons
• Analysis of the J/psi --> pi^0 gamma^* transition form factor

Cited by in corpus (1)

• QCD analysis of the $P$-wave charmonium electromagnetic Dalitz decays $h_c\to {\eta }^{(\prime )}{\ell }^{+}{\ell }^{-}$