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Search for Charmonium States Decaying to J/psi gamma gamma Using Initial-State Radiation Events

The BABAR Collaboration·B. Aubert
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Abstract

We study the processes e+e- -> (J/psi gamma gamma) gamma and e+e- -> (J/psi pi- pi+) gamma where the hard photon radiated from an initial e+e- collision with center-of-mass (CM) energy near 10.58 GeV is detected. In the final state J/psi gamma gamma we consider J/psi pi0, J/psi eta, chi_{c1} gamma, and chi_{c2} gamma candidates. The invariant mass of the hadronic final state defines the effective e+e- CM energy in each event, so these data can be compared with direct e+e- measurements. We report 90% CL upper limits for the integrated cross section times branching fractions of the J/psi gamma gamma channels in the Y(4260) mass region.

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The BABAR Collaboration, B. Aubert. 2006-08-01. Search for Charmonium States Decaying to J/psi gamma gamma Using Initial-State Radiation Events. https://arxiv.org/abs/hep-ex/0608004

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