Measurement of the Branching Fraction of B0bar-$>$ D*+ Lepton Neutrino

We present a measurement of the branching fraction of semileptonic anti-B0 meson decays to D*+ meson, lepton, and anti-neutrino using 476 million B-meson anti-B-meson pairs. The data sample collected with the BABAR detector at the PEP-II asymmetric-energy B-Factory at SLAC National Accelerator Laboratory. The anti-B0 mesons are reconstructed using a novel technique, partial reconstruction, where the D0 mesons are not reconstructed. The D*+ mesons are detected only through the soft pion daughter from the decay D*+ to D0 pi+. We use a single and double tag method to measure the semileptonic branching fraction. This precise measurement plays a prominent role in high energy physics particularly in heavy flavor physics.