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arXiv · 0907.1681

Model-independent search for the decay B -> l nu gamma

The BABAR Collaboration·B. Aubert
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Abstract

We present a search for the radiative leptonic decay B+ -> l+ nu gamma, where l=e,mu, using a data sample of 465 million B-meson pairs collected by the BABAR experiment. In this analysis, we fully reconstruct the hadronic decay of one of the B mesons in Upsilon(4S) -> B+B- decays, then search for evidence of B+ -> l+ nu gamma in the rest of the event. We observe no significant evidence of signal decays and report model-independent branching fraction upper limits of BR(B+ -> e+ nu gamma)<17e-6, BR(B+ -> mu+ nu gamma)< 24e-6, and BR(B+ -> l+ nu gamma)<15.6e-6 (l= e or mu), all at the 90% confidence level.

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The BABAR Collaboration, B. Aubert. 2009-12-17. Model-independent search for the decay B -> l nu gamma. https://doi.org/10.1103/physrevd.80.111105

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