Measurement of the decay amplitudes and branching fractions of B->J/psi K-* and B->J/psi K decays

Using data taken with the CLEO II detector at the Cornell Electron Storage Ring, we present the first full angular analysis in the color-suppressed modes B0 → J/ψ K*0 and B+ → J/ψ K*+. This leads to a complete determination of the decay amplitudes of these modes including the longitudinal polarization TL/Γ = 0.52 ± 0.07 ± 0.04 and the P wave component |P|2 = 0.16 ± 0.08 ± 0.04. In addition, we update the branching fractions for B → J/ψ K and B → J/ψ K*.