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arXiv · hep-ex/0611041

Search for Invisible Decay of the $Υ(1S)$

The Belle Collaboration·O. Tajima·H. Hayashii·M. Hazumi·K. Inami·Y. Iwasaki·S. Uehara
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Abstract

We report results of a search for the invisible decay of the Upsilon(1S) via the Upsilon(3S)->pi+pi-Upsilon(1S) transition using a data sample of 2.9 fb^{-1} at the Upsilon(3S) resonance. The data were collected with the Belle detector at the KEKB asymmetric-energy e+e- collider. No signal is found, and an upper limit for the branching fraction at the 90% confidence level is determined to be B(Upsilon(1S)->invisible) < 2.5x10^{-3}.

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The Belle Collaboration, O. Tajima, H. Hayashii, M. Hazumi, K. Inami, Y. Iwasaki, S. Uehara. 2007-03-28. Search for Invisible Decay of the $Υ(1S)$. https://doi.org/10.1103/physrevlett.98.132001

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