Radiative corrections to hard spectator scattering in B → ππ decays

We present the calculation of the next-to-leading corrections to the tree amplitudes which appear in the description of non-leptonic B-decays in the factorization approach. These corrections, together with radiative corrections to the jet functions, represent the full next-to-leading contributions to the dominant hard spectator scattering term generated by operators O1,2 in the decay amplitudes. Using obtained analytical results we estimate B → ππ branchings fractions in the physical ( or BBNS) factorization scheme. We have also found that the imaginary part generated in the hard spectator scattering term is rather large compared to the imaginary part of the vertex contribution. ∗ On leave of absence from St. Petersburg Nuclear Physics Institute, 188350, Gatchina, Russia