Enhancement of preasymptotic effects in inclusive beauty decays

We extend Voloshin's recent analysis of charmed and beauty hyperon decays b ased on SU(3) symmetry and heavy quark effective theory, by introducing a r ather moderate model-dependence, in order to obtain more predictive power, e.g. the values of lifetimes of the (Lambda(b), Xi(b)) hyperon triplet and the lifetime of Omega(b). In this way we obtain an improvement of the ratio tau(Lambda(b))/tau(B-d(0)) similar to 0.9 and the hierarchy of lifetimes t au(Lambda(b)) similar or equal to tau(Xi(b)(0)) < tau(Xi(b)(-)) < tau(Omega (b)) with lifetimes of Xi(b)(-) and Omega(b) exceeding the lifetime of Lamb da(b) by 22% and 35%, respectively. (C) 1999 Published by Elsevier Science B.V. All rights reserved.