TTP98-14 Two-loop QCD corrections to semileptonic b decays at an intermediate recoil

We present complete O(alpha_s^2) corrections to the decay b–>c+l+nu at the point where the invariant mass of the leptons sqrt{q^2} equals the c quark mass. We use this result, together with previously obtained corrections at the ends of the q^2 spectrum, to estimate the total width of the semileptonic b–>c decay with O(alpha_s^2) accuracy, essential for the |V_{cb}| determination.