B Meson Form Factors and Exclusive Decays

Abstract

We present results for the $B\to \pi$ and $D\to \pi$ form factors derived from QCD sum rules on the light-cone. Our predictions are compared with experiment and used to extract the quark mixing parameter $|V_{ub}|$ from a recent CLEO measurement of $B\text{ra}\pi l^{+}\nu$. Furthermore, we discuss the factorization approximation for exclusive nonleptonic matrix elements, and describe a first QCD estimate of the nonfactorizable contribution to the amplitude of $B\to J/\psi K$.

Comments: 14 pages, Latex, epsf.sty, 3 uuencoded .ps figures; invited talk presented by R. Rückl at the Workshop `Beauty 95', Oxford, July 9-14,1995, to appear in the proceedings