اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدPrecision calculations of $B to V$ form factors in QCD
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Applying the vacuum-to-$B$-meson correlation functions with an interpolating current for the light vector meson we construct the light-cone sum rules (LCSR) for the effective form factors $xi_{parallel}(n cdot p)$, $xi_{perp}(n cdot p)$, $Xi_{parallel}(tau, n cdot p)$ and $Xi_{perp}(tau, n cdot p)$, defined by the corresponding hadronic matrix elements in soft-collinear effective theory (SCET), entering the leading-power factorization formulae for QCD form factors responsible for $B to V ell bar u_{ell}$ and $B to V ell bar ell$ decays at large hadronic recoil at next-to-leading-order in QCD. The light-quark mass effect for the local SCET form factors $xi_{parallel}(n cdot p)$ and $xi_{perp}(n cdot p)$ is also computed from the LCSR method with the $B$-meson light-cone distribution amplitude $phi_B^{+}(omega, mu)$ at ${cal O}(alpha_s)$. Furthermore, the subleading power corrections to $B to V$ form factors from the higher-twist $B$-meson light-cone distribution amplitudes are also computed with the same method at tree level up to the twist-six accuracy. Having at our disposal the LCSR predictions for $B to V$ form factors, we further perform new determinations of the CKM matrix element $|V_{ub}|$ from the semileptonic $B to rho , ell , bar u_{ell}$ and $B to omega , ell , bar u_{ell}$ decays, and predict the normalized differential branching fractions and the $q^2$-binned $K^{ast}$ longitudinal polarization fractions of the exclusive rare $B to K^{ast} , u_{ell} , bar u_{ell}$ decays.
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