Document Type



We study the processes γγ → ηc → η'K+K, η'π+π, and ηπ+π using a data sample of 519 fb−1 recorded with the BABAR detector operating at the SLAC PEP-II asymmetric-energy e+e collider at center-of-mass energies at and near the ϒ(nS) (n = 2, 3, 4) resonances. This is the first observation of the decay ηc → η'K+K and we measure the branching fraction Γ(ηc → η' K+K)=(Γ(ηcη'π+π) = 0.644 ± 0.039stat 0.032sys. Significant interference is observed between γγ → ηc → ηπ+π and the nonresonant two-photon process γγ → ηπ+π. A Dalitz plot analysis is performed of ηc decays to η'K+K,η'π+π, and ηπ+π. Combined with our previous analysis of ηc KK̅ π, we measure the K * 0 (1430) parameters and the ratio between its η' K and πK couplings. The decay ηc → η' π+π is dominated by the f0(2100) resonance, also observed in J=ψ radiative decays. A new a0(1700) → ηπ resonance is observed in the ηcηπ+π- channel. We also compare ηc decays to η and η' final states in association with scalar mesons as they relate to the identification of the scalar glueball.

Digital Object Identifier (DOI)

APA Citation

Lees, J. P., Poireau, V., Tisserand, V., Grauges, E., Palano, A., Eigen, G., Brown, D. N., Kolomensky, Yu. G., Fritsch, M., Koch, H., Schroeder, T., Cheaib, R., Hearty, C., Mattison, T. S., McKenna, J. A., So, R. Y., Blinov, V. E., Buzykaev, A. R., Druzhinin, V. P., … Wu, S. L. (2021). Light meson spectroscopy from Dalitz plot analyses of . Physical Review D, 104(7).

Included in

Physics Commons