PHENOMENOLOGICAL CONSTRAINTS ON (LAMBDA)OVER-BAR AND LAMBDA(1)

Combining the experimental data on the inclusive decays D --> X enu, B --> X enu, and B --> X --> tau nu, we find severe constraints on the LAMBDABAR and lambda1 parameters of the heavy quark effective theory. In particular, we get LAMBDABAR < 0.7 GeV. Our constraints further imply m(c) greater-than-or-equal-to 1.43 GeV and M(b) greater-than-or-equal-to 4.66 GeV. We discuss future prospects of improving these bounds and their phenomenological implications.