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Dear all, 

I have prepared an abstract for LP2005, which should be sent to the PAC
early next week. Could you please let me know if you have any
corrections/suggestions/comments/etc. 

Thanks, Concezio. 


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Measurements of charmless semileptonic B decays and determination of
|Vub|
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Charmless semileptonic decays, $B \to X_u \ell\nu$, are studied on a
sample of 215 million BB decays recorded with the BABAR detector, in
events where the decay of the second B meson is fully reconstructed.

Inclusive charmless decays are selected in kinematic regions where the
dominant background from semileptonic B decays to charm is reduced by
requirements on the hadronic mass Mx, the electron energy El, and the
momentum transfer q^2. Signal efficiency and background are estimated
from Monte Carlo simulation and data control samples and used to measure
partial branching fractions for $B\to X_{u} e \nu$. The CKM matrix
element $|V_{ub}|$ is determined by using theoretical calculations.
Theoretical uncertainties in this extrapolation are studied in detail,
and reduced by using the inclusive photon spectrum from $b \to s \gamma$
transitions and the moments of the lepton energy and hadronic invariant
mass in semileptonic B decays to charm.

In addition, we have isolated various exclusive charmless decay modes.
>From the resulting small sample of exclusive decays, such as $B \to \pi
(\rho, \omega, \eta) \ell \nu$ we have obtained preliminary exclusive
branching fraction measurements.
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