Search for B+ -˃ l(+)nu(l)gamma decays with hadronic tagging using the full Belle data sample

Abstract

We search for the decay B+ -˃ l(+)nu(l)gamma with l(+) = e(+) or mu(+) using the full Belle data set of 772 x 10(6) B (B) over bar pairs, collected at the Y(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+ -˃ l(+)nu(l)gamma decay in the remainder of the event. We observe no significant signal within the phase space of E-gamma(sig) ˃ 1 GeV and obtain upper limits of B(B+ -˃ e(+)nu(e)gamma) ˂ 6.1 x 10(-6), B(B+ -˃ mu(+)nu(mu)gamma) ˂ 3.4 x 10(-6), and B(B+ -˃ l(+)nu(l)gamma) ˂ 3.5 x 10(-6) at 90% credibility level.