Using a sample of (225.3±2.8)×106 J/ψ decays collected with the BESIII detector at BEPCII, searches for invisible decays of η and η′ in J/ψ→η and η′ are performed. Decays of →K+K- are used to tag the η and η′ decays. No signals above background are found for the invisible decays, and upper limits at the 90% confidence level are determined to be 2.6×10-4 for the ratio B(η→invisible) B(η→γγ) and 2.4×10-2 for B(η′→invisible)B(η ′→γγ). These limits may be used to constrain light dark matter particles or spin-1 U bosons.
|Original language||English (US)|
|Journal||Physical Review D - Particles, Fields, Gravitation and Cosmology|
|State||Published - Jan 24 2013|
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© 2013 American Physical Society.