Measurement of the Electron Energy Spectrum and its Moments in Inclusive B->X e nu Decays

TL;DR

This paper measures the inclusive electron energy spectrum in semileptonic B meson decays, providing moments and branching fractions crucial for understanding B decay dynamics and testing the Standard Model.

Contribution

It presents the first measurement of the electron energy spectrum moments and branching fraction in B decays with detailed energy cut-offs, using a large data sample from BABAR.

Findings

Partial branching fraction: (10.36 +-0.06(stat.) +-0.23(sys))% for E_e>0.6 GeV

First, second, and third moments of the spectrum determined

Spectrum moments measured for various energy cut-offs

Abstract

We report a measurement of the inclusive electron energy spectrum for semileptonic decays of B mesons in a data sample of 52 million Y4S -> BBar decays collected with the BABAR detector at the PEP-II asymmetric-energy B-meson factory at SLAC. We determine the branching fraction, first, second, and third moments of the spectrum for lower cut-offs on the electron energy between 0.6 and 1.5 GeV. We measure the partial branching fraction to be Br(B -> X e nu, E_e>0.6 GeV) = (10.36 +-0.06(stat.) +-0.23(sys))%.