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arXiv · 0709.3371

Search for the C-parity violating process J/psi->gamma gamma via psi(2S)->pi+pi- J/psi

M. Ablikim·J. Z. Bai
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Abstract

Using 14.0\times 10^6 ψ(2S) events collected with the BES-II detector, the C-parity violating process J/psi->gamma gamma via psi(2S)->pi+pi- J/psi is studied. We determine a new upper limit for the J/psi->gamma gamma branching ratio of B(J/psi->gamma gamma)<2.2\times 10^{-5} at the 90% C.L., which is about 20 times lower than the previous measurement.

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M. Ablikim, J. Z. Bai. 2007-09-21. Search for the C-parity violating process J/psi->gamma gamma via psi(2S)->pi+pi- J/psi. https://doi.org/10.1103/physrevd.76.117101

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