Precision calculations of B→V form factors from soft-collinear effective theory sum rules on the light-cone

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 ξ_∥(n·p), ξ_⊥(n·p), Ξ_∥(τ,n·p) and Ξ_⊥(τ,n·p), defined by the corresponding hadronic matrix elements in soft-collinear effective theory (SCET), entering the leading-power factorization formulas for QCD form factors responsible for B→Vν_ and B→V decays at large hadronic recoil at next-to-leading-order in QCD. The evanescent-operator approach for the perturbative matching of the effective operators from SCETI→HQET is employed in the determination of the hard-collinear functions entering the SCET factorization formulas for the vacuum-to-B-meson correlation functions. The light-quark mass effect for the local SCET form factors ξ_∥(n·p) and ξ_⊥(n·p) is also computed from the LCSR method with the B-meson light-cone distribution amplitude φB⁺(ω,μ) at O(αₛ). Furthermore, the subleading power corrections to B→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. Employing the two different models for the B-meson light-cone distribution amplitudes consistent with QCD equations of motion, we observe that the higher-twist corrections to B→V form factors are dominated by the two-particle twist-five distribution amplitude gB^-(ω,μ), in analogy to the previous observation for B→P form factors. Having at our disposal the LCSR predictions for B→V form factors, we further perform new determinations of the Cabibbo-Kobayashi-Maskawa (CKM) matrix element |Vub| from the semileptonic B→ρν_ and B→ων_ decays, and predict the normalized differential branching fractions and the q²-binned K* longitudinal polarization fractions of the exclusive rare B→K*ν_ν_ decays.