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arXiv · hep-ex/0408144

Search for B -> tau nu at Belle

Abstract

We present a search for the decay B -> tau nu in a 140 fb^-1 data sample collected at the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric B factory. Combinatorial and continuum backgrounds are suppressed by selecting a sample of events with one fully reconstructed B. The decay products of the other side B in the event are analyzed to search for a B -> tau nu decay. We find no significant evidence for a signal and set a 90% confidence level upper limit of Br(B -> tau nu) < 2.9 * 10^-4. All results are preliminary.

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K. Abe. 2004-08-30. Search for B -> tau nu at Belle. https://arxiv.org/abs/hep-ex/0408144

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