### Abstract

We present the first evidence for the production of [Formula Presented] states in the four-photon cascade, [Formula Presented] [Formula Presented] [Formula Presented] [Formula Presented] followed by the [Formula Presented] annihilation into [Formula Presented] or [Formula Presented] The signal has a significance of 10.2 standard deviations. The measured product branching ratio for these five decays, [Formula Presented] is consistent with the theoretical estimates. The data are dominated by the production of one [Formula Presented] state consistent with the [Formula Presented] assignment. Its mass is determined to be [Formula Presented] MeV, which is consistent with the predictions from potential models and lattice QCD calculations. We also searched for [Formula Presented] [Formula Presented] followed by either [Formula Presented] or [Formula Presented] We find no evidence for such decays and set upper limits on the product branching ratios.

Original language | English (US) |
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Journal | Physical Review D - Particles, Fields, Gravitation and Cosmology |

Volume | 70 |

Issue number | 3 |

DOIs | |

State | Published - 2004 |

### ASJC Scopus subject areas

- Nuclear and High Energy Physics
- Physics and Astronomy (miscellaneous)

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## Cite this

*Physical Review D - Particles, Fields, Gravitation and Cosmology*,

*70*(3). https://doi.org/10.1103/PhysRevD.70.032001