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تسجيل مستخدم جديد$B to rho l bar u$ and $omega l bar u$ in and beyond the Standard Model: Improved predictions and $|V_{ub}|$
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We revisit the experimental and theoretical status of $B to rho l bar{ u}$ and $B to omega l bar{ u}$ decays. We perform a combined fit of averaged spectra from Belle and Babar measurements with prior light cone sum rule calculations, in order to obtain more precise predictions over the full $q^2$ range. The extracted values of $|V_{ub}|$ from these combined fits exhibit smaller uncertainty compared to previous extractions from $B to rho l bar{ u}$ and $B to omega l bar{ u}$ decays and the central values are found to be smaller than values extracted from $B to pi l u$ or inclusive measurements. We use our fit results to obtain more precise predictions in and beyond the Standard Model for the lepton universality ratios $R(rho)$ and $R(omega)$, as well as several angular observables that are sensitive to the full $q^2$ distribution, such as the longitudinal polarization of the vector meson, the $tau$ polarization, and its forward-backward asymmetry.
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