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arXiv · hep-ex/0205100

Measurement of χ_{c2} Production in Two-Photon Collisions

Belle Collaboration·K. Abe
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Abstract

The production of the χ_{c2} charmonium state in two-photon collisions has been measured with the Belle detector at the KEKB e^+e^- collider. A clear signal for χ_{c2} --> γJ/ψ, J/ψ--> l^+l^- is observed in a 32.6fb^{-1} data sample accumulated at center-of-mass energies near 10.6GeV, and the product of its two-photon decay width and branching fraction is determined to be Γ_{γγ}(χ_{c2})B(χ_{c2} --> γJ/ψ) B(J/ψ--> l^+l^-)= 13.5 +/- 1.3(stat.) +/- 1.1(syst.)eV.

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Belle Collaboration, K. Abe. 2002-05-30. Measurement of χ_{c2} Production in Two-Photon Collisions. https://doi.org/10.1016/s0370-2693(02)02104-4

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