EXTRACTION OF A(1) AND A(2) FROM B-]PSI-K(K-ASTERISK), D(D-ASTERISK)PI(RHO) DECAYS

Based on the factorization approach, we show that the CLEO data for the ratio (B K*)/ (B K) and the CDF measurement of the fraction of longitudinal polarization in B K* can be accounted for by the heavy-flavor-symmetry approach for heavy-light form factors provided that the form factor F0 behaves as a constant, while the q2 dependence is of the monopole form for F1, A0, A1, and of the dipole behavior for A2 and V. This q2 extrapolation for form factors is further supported by B K* data and by a recent QCD sum-rule analysis. We then apply this method to B D(D*) decays to extract the parameters a1 and a2. It is found that a1(B D(*))=1.01 0.06 and a2(B D(*))=0.23 0.06. Our result a2/a1=0.22 0.06 thus significantly improves the previous analysis that leads to a2/a1=0.23 0.11. We argue that, contrary to what is anticipated from the leading 1/Nc expansioon, the sign of a2(B K(*)) should be positive and a2(B K(*))a2(B D(*)). © 1995 The American Physical Society.