| Abstract |
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We present a measurement of moments of the inclusive hadronic-mass
and -energy spectrum in semileptonic Bbar -> X_c l- nubar decays.
This study is based on a sample of 232 million Y(4S) -> B Bbar decays
recorded by the BABAR detector at the PEP-II e+e- -storage rings.
We reconstruct the semileptonic decay by identifying a lepton in events
tagged by a fully reconstructed hadronic decay of the second B meson.
We report preliminary results for the moments with k=1,...,6
and with k=2,4,6 and n_X^2 = m_X^2 c^4 - 2 Lambdatilde E_X +
Lambdatilde^2, with m_X the mass of the hadronic system, E_X its energy,
and Lambdatilde a constant of 0.65 GeV, for different minimal lepton
momenta between 0.8 and 1.9 GeV/c measured in the B-meson rest frame.
These are predicted in the framework of a Heavy Quark Expansion (HQE),
which allows the extraction of the total semileptonic branching fraction,
the CKM-matrix element |V_{cb}|, and the quark masses m_b and m_c, together
with the dominant non-perturbative HQE parameters. We find as preliminary
results |V_{cb}| = (41.88 +- 0.81) 10^-3 and m_b = (4.552 +- 0.055) GeVc^2.
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