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The eta_c(2980) formation in two-photon collisions at LEP energies

The DELPHI Collaboration·J. Abdallah
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Abstract

eta_c(2980) production in gamma-gamma interactions has been detected via its decays into K0_s K+/- pi-/+, K+ K- K+ K- and K+ K- pi+ pi- in the data taken with the DELPHI detector at LEP1 and LEP2 energies. The two-photon radiative width averaged over all observed decay channels is Γ_{γγ} = 13.9 +/- 2.0 (stat.) +/- 1.4 (syst.) +/- 2.7 (BR) keV. No direct decay channel eta_c -> pi+ pi- pi+ pi- has been observed. An upper limit $Γ_{γγ}$ < 5.5 keV at 95% confidence level has been evaluated for this decay mode.

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The DELPHI Collaboration, J. Abdallah. 2003-11-01. The eta_c(2980) formation in two-photon collisions at LEP energies. https://doi.org/10.1140/epjc%2Fs2003-01384-0

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