Study of $\eta_c$ Production in Two Photon Collisions

Production of theηc meson ine+e− quasireal two photon collisions has been looked for in three channels. The data were obtained from an integrated luminosity of 189 pb−1. Anηc signal is observed in two decay modes (Ks0K±π∓,π+π-π+π-) with a combined statistical significance of 3.5 standard deviations. Using the knownηc branching ratios to these channels and toK+K-π+π- the combined partialηc width to γγ isΓγγ(ηc). The first error is statistical, and the second one includes the systematic and branching ratio errors. Calculated as an upper limit we obtainΓγγ(ηc) (95% C.L., including the systematic error).

ELECTRON POSITRON: COLLIDING BEAMS
COLLIDING BEAMS: ELECTRON POSITRON
ELECTRON POSITRON: INELASTIC SCATTERING
INELASTIC SCATTERING: ELECTRON POSITRON
EXCHANGE: TWO-PHOTON
TWO-PHOTON: EXCHANGE
PHOTON PHOTON: EXCLUSIVE REACTION
ETA/C(2980): ELECTROPRODUCTION
ELECTROPRODUCTION: ETA/C(2980)
ETA/C(2980): NONLEPTONIC DECAY

References(16)

Figures(0)

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