  We calculate the amplitudes and the cross sections of the charm dissociation
processes J/\psi \pi => D \bar D, D* \bar D, D \bar D*, D* \bar D* within a
relativistic constituent quark model. We consistently account for the
contributions coming from both the box and triangle diagrams that contribute to
the dissociation processes. The cross section is dominated by the D* \bar D and
D* \bar D* channels. When summing up the four channels we find a maximum total
cross section of about 2.3 mb at sqrt(s) \approx 4.1 GeV. We compare our
results to the results of other model calculations.
