New exact heavy quark sum rules

Considering nonforward scattering amplitude off the heavy quark in the Small Velocity limit two exact superconvergent sum rules are derived. The first is the sum rule for spin of the light cloud and leads to the lower bound rho (2) > 3/4 for the slope of the Isgur-Wise function. It also provides the rationale for the fact that the vector heavy flavor mesons are heavier than the pseudoscalar ones. A spin-nonsinglet analogue <(<Sigma>)over bar> of <(<Lambda>)over bar> = M(B) - m(b) is introduced. (C) 2001 Published by Elsevier Science B.V.