Upper limit on the η → π + π − branching ratio with the KLOE detector . The KLOE Collaboration

نویسندگان

  • V. Bocci
  • P. Branchini
  • F. Ceradini
  • G. Chiefari
  • A. De Santis
  • B. Di Micco
  • A. Farilla
  • M. L. Ferrer
  • P. Franzini
  • E. Gorini
  • E. Graziani
  • F. Lacava
  • G. Lanfranchi
  • P. Massarotti
  • A. Passeri
  • P. Santangelo
  • E. Santovetti
چکیده

We have searched with the KLOE detector for the P and CP violating decay η → ππ in a sample of 1.55 × 10 η’s from the decay φ → ηγ of φ-mesons produced in ee annihilations at DAΦNE. No signal is found. We obtain the upper limit BR(η → ππ)< 1.3×10 at 90% confidence level.

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تاریخ انتشار 2004