CORRECTIONS OF ORDER LAMBDA(2)(QCD) M(C)(2) TO INCLUSIVE RARE B-DECAY/

We calculate non-perturbative O(Lambda(QCD)(2)/m(c)(2)) corrections to the dilepton invariant mass spectrum and the forward-backward charge asymmetry in B --> X(s)e(+)e(-) decay using a heavy quark expansion ap proach. The method has recently been used to estimate long-distance ef fects in B --> X-s gamma. We generalize this analysis to the case of n on-vanishing photon invariant mass, q(2) not equal 0, relevant for the rare decay mode B --> X(s)e(+)e(-). In the phenomenologically interes ting q(2) region away from the c (c) over bar resonances, the heavy qu ark expansion approach should provide a reasonable description of poss ible non-perturbative corrections. In particular this picture is prefe rable to the model-dependent approach relying on the tails of Breit-Wi gner resonances, which has been employed so far in the literature to a ccount for these effects. We find that the O(Lambda(QCD)(2)/m(c)(2)) c orrections to the dilepton invariant mass spectrum and to the forward- backward asymmetry in B --> X(s)e(+)e(-) amount to several percent at most for q(2)/m(b)(2) less than or similar to 0.3 and q(2)/m(b)(2) gre ater than or similar to 0.6. The O(Lambda(QCD)(2)/m(c)(2)) correction to the B --> X-s gamma decay rate is also computed and found to be +3% , which agrees in magnitude with previous calculations. Finally, we co mment on long-distance effects in B --> X-x nu<(nu)over bar>, which in this case are extremely suppressed due to the absence of virtual phot on contributions. (C) 1998 Elsevier Science B.V.