Search for B+ →a+νaγ decays with hadronic tagging using the full Belle data sample

Abstract

We search for the decay B+→+νγ with +=e+ or μ+ using the full Belle data set of 772×106BB¯ pairs, collected at the Υ(4S) resonance with the Belle detector at the KEKB asymmetric-energy e+e- collider. We reconstruct one B meson in a hadronic decay mode and search for the B+→+νγ decay in the remainder of the event. We observe no significant signal within the phase space of Eγsig>1GeV and obtain upper limits of B(B+→e+νeγ)<6.1×10-6, B(B+→μ+νμγ)<3.4×10-6, and B(B+→+νγ)<3.5×10-6 at 90% credibility level.