THE PHENOMENOLOGY OF INCLUSIVE HEAVY-TO-LIGHT SUM-RULES

By calculating the O(alpha(s)) corrections to inclusive heavy-to-light sum rules we find model independent upper and lower bounds on form fa ctors for (B) over bar --> <pi l(nu)over bar> and (B) over bar --> <rh o l(nu)over bar>. We use the bounds to rule out model predictions. Som e models violate the bounds only for certain ranges of sum rule input parameters. <(Lambda)over bar> similar or equal to M-B - m(b) and lamb da(1), or for certain choices of model parameters, while others obey o r violate the bounds irrespective of the inputs. We discuss the reliab ility and convergence of the bounds, point out their utility for extra cting V-ab, and derive from them a new form factor scaling relation. ( C) 1998 Elsevier Science B.V.