Model-independent bounds on new physics effects in non-leptonic tree-level decays of B-mesons

We present a considerably improved analysis of model-independent bounds on new physics effects in non-leptonic tree-level decays of B-mesons. Our main finding is that contributions of about +/- 0.1 to the Wilson coefficient of the colour-singlet operator Q(2) of the effective weak Hamiltonian and contributions in the range of +/- 0.5 (both for real and imaginary part) to Q(1) can currently not be excluded at the 90% C.L. . Effects of such a size can modify the direct experimental extraction of the CKM angle gamma by up to 10(degrees) and they could lead to an enhancement of the decay rate difference Gamma(d) of up to a factor of 5 over its SM value - a size that could explain the D0 dimuon asymmetry. Future more precise measurements of the semi-leptonic asymmetries aslq and the lifetime ratio tau (B-s)/tau (B-d) will allow to shrink the bounds on tree-level new physics effects considerably. Due to significant improvements in the precision of the non-perturbative input we update all SM predictions for the mixing obervables in the course of this analysis, obtaining: M-s = (18.77 +/- 0.86) ps(-1), M-d = (0.543 +/- 0.029) ps(-1), Gamma(s) = (9.1 +/- 1.3) . 10(-2) ps(-1), Gamma d = (2.6 +/- 0.4) . 10(-3) ps(-1), aslq = (2.06 +/- 0.18) . 10(-5) and asld = (-4.73 +/- 0.42) . 10(-4).