Bounding Heavy Meson Form Factors Using Inclusive Sum Rules
  We utilize inclusive sum rules to construct both upper and lower bounds on the form factors for B to D, D*, rho, pi, omega, K and K* semi-leptonic and radiative decays. We include the leading nonperturbative 1/E corrections and point out cases when alpha_s corrections are equally important. We compute the alpha_s correction to the lower bound on the B to D* form factor f(w) at zero recoil, thereby constraining its normalization f(1) to within 6-8% of the upper bound. We show that the B to rho form factor a_+ is suppressed at small momentum transfer by either a factor of 1/E or alpha_s. These bounds can be used to rule out phenomenological models as well as to determine values for the CKM matrix elements once radiative corrections are included. 
C. Glenn Boyd (UCSD) and Ira Z. Rothstein (UCSD)