Open charm contributions to the E1 transitions of $$\psi (3686)$$ ψ ( 3686 ) and $$\psi (3770)\rightarrow \gamma \chi _{cJ}$$ ψ ( 3770 ) → γ χ c J

Abstract

The E1 transitions of ψ(3686) and ψ(3770) → γ χ cJ are investigated in a non-relativistic effective field theory (NREFT) where the open charm effects are included systematically as the leading corrections. It also allows a selfconsistent inclusion of the S-D mixing in the same framework. We are able to show that the open charm contributions are essential for understanding the rather unexpected discrepancies between the non-relativistic leading order calculations and the experimental data for these two low-lying states.

Open Charm Contributions to the E1 Transitions of \(\psi \)(3686) and \(\psi \)(3770) \( \to \) \(\gamma \chi _{cJ}\)

“…The full results in both SU(2) and SU(3) schemes can be found in Ref. [11]. In both of the schemes the tree-level transitions play dominant role in all exclusive contributions as expected and they are compatible with the results for quark model.…”

“…Calculation results in both SU(2) and SU(3) schemes can be found in Ref. [11]. The results are compared to three particular model calculations, i.e.…”

“…The detailed Lagrangians used here are not included here for simplicity and they can be found in Ref. [11]. In the calculation of the loop diagrams divergence appears in the mixing amplitudes in Fig.…”

Muon pair production in radiative decays of heavy quarkonia

“…Among such processes one can name, for example, lepton pair production in χ cJ → J/ψ and χ bJ → Υ decays. In [15] it was shown that the branching fractions of these decays and distributions over the invariant mass of ( ) pair can be calculated using very general assumptions on the basis of experimentally known branching fractions of the corresponding radiative decays χ cJ → J/ψγ and χ bJ → Υγ (see also [16][17][18][19]). Currently only χ c1,2 → J/ψee process was studied experimentally [20].…”

Modeling charmonium- η decays of JPC=1−− higher charmonia

“…The Cornell spin-independent potential is an approximate heavy quark spin symmetry (HQSS) within cc systems. Deviations with experiments can be observed in such potential models due to HQSS breaking effects [8,9]. One possible source of breaking HQSS is the spin-dependent potential which introduces relativistic corrections to the Cornell potential model.…”