Exclusive Semileptonic and Rare B-Meson Decays in QCD

Abstract

We present the first complete results for the semileptonic and rare radiative form factors of B-mesons weak decay into a light vector-meson (rho, omega, K*, phi) in the light-cone sum-rule approach. The calculation includes radiative corrections, higher-twist corrections and SU(3)-breaking effects. The theoretical uncertainty is investigated in detail. A simple parametrization of the form factors is given in terms of three parameters each. We find that the form factors observe several relations inspired by heavy-quark symmetry.

Figures (9)

• Figure 1: The leading-order diagram (a) and one-loop radiative corrections (b--f).
• Figure 2: The higher-twist contributions.
• Figure 3: Light-cone sum-rule results for $B_{u,d}\to\,$vector-meson form factors. Renormalization scale for $T_i$ is $\mu = m_b = 4.8\,$GeV. Further parameters: $m_b = 4.8\,$GeV, $s_0 = 33.5\,$GeV$^2$, $M^2 = 6\,$GeV$^2$.
• Figure 4: Light-cone sum-rule results for $B_s\to\,$vector-meson form factors. Renormalization scale for $T_i$ is $\mu = m_b = 4.8\,$GeV. Further parameters: $m_b = 4.8\,$GeV, $s_0 = 34.5\,$GeV$^2$, $M^2 = 6\,$GeV$^2$.
• Figure 5: Separate contributions to the form factors $A_1^\rho$ and $A_1^{K^*}$.