Tau polarization effects in the CNGS ντ appearance experiments ⁎

We studied τ polarization effects on the decay distributions of τ produced in the CNGS ντ appearance experiments. We show that energy and angular distributions for the decay products in the laboratory frame are significantly affected by the τ polarization. Rather strong azimuthal asymmetry about the τ momentum axis is predicted, which may have observable consequences in experiments even with small statistics.