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Search for B -> tau nu and B -> K nu nubar Decays with a Fully Reconstructed B at Belle

K. Abe
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Abstract

We present a search for the decays B -> tau nu and B -> K nu nubar in a 253 fb^-1 data sample collected at the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric energy B factory. Combinatorial and continuum backgrounds are suppressed by selecting a sample of events with one fully reconstructed B. The decay products of the B on the other side of the event are analyzed to search for B -> tau nu and B -> K nu nubar decays. We find no significant evidence for a signal and set 90% confidence level upper limits of B(B -> tau nu) < 1.8*10^-4 and B(B -> K nu nubar) < 3.6*10^-5.

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K. Abe. 2005-07-08. Search for B -> tau nu and B -> K nu nubar Decays with a Fully Reconstructed B at Belle. https://arxiv.org/abs/hep-ex/0507034

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