# Hadronic loop contributions to $J-ψ$ and $ψ^prime$ radiative decays into $γη c$ or $γη c^prime$ - High Energy Physics - Phenomenology

Hadronic loop contributions to $J-ψ$ and $ψ^prime$ radiative decays into $γη c$ or $γη c^prime$ - High Energy Physics - Phenomenology - Download this document for free, or read online. Document in PDF available to download.

Abstract: Intermediate hadronic meson loop contributions to $J-\psi$, $\psi^\prime \to\gamma\eta c$ $\gamma\eta c^\prime$ are studied apart from the dominant M1transitions in an effective Lagrangian approach. Due to the property of theunique antisymmetric tensor coupling in $V\to VP$, the hadronic looptransitions provide explicit corrections to the M1 transition amplitudesderived from the naive -quenched- $c\bar{c}$ transitions via the coupling formfactors. This mechanism interfering with the M1 transition amplitudes naturallyaccounts for the deviations from the Godfrey-Isgur model predictions in$J-\psi$ and $\psi^\prime\to \gamma\eta c$. It also predicts a small branchingratio of $\psi^\prime\to \gamma\eta c^\prime$, which can be examined byexperimental measurements at BES and CLEO-c.

Author: Gang Li, Qiang Zhao

Source: https://arxiv.org/