Measurement of Differential Branching Fractions of Inclusive <i>B</i> → <i>X</i><sub>u</sub><i>l</i><SUP>+</SUP><i>v<sub>l</sub></i> Decays

Abstract

The first measurements of differential branching fractions of inclusive semileptonic B -> X(u)l(+)v(l) decays are performed using the full Belle data set of 711 fb(-1) of integrated luminosity at the gamma(4S) resonance and for l = e, mu. With the availability of these measurements, new avenues for future shape-function modelindependent determinations of the Cabibbo-Kobayashi-Maskawa matrix element vertical bar V-ub vertical bar, can be pursued to gain new insights in the existing tension with respect to exclusive determinations. The differential branching fractions are reported as a function of the lepton energy, the four-momentum-transfer squared, light-cone momenta, the hadronic mass, and the hadronic mass squared. They are obtained by subtracting the backgrounds from semileptonic B -> X(c)l(+)v(l), decays and other processes, and corrected for resolution and acceptance effects.