Projectile fragmentation at relativistic energies: A possibility to determine the viscosity of nuclear matter

Up to now, the results on nuclear viscosity are rather contradictory. Value s of the dissipation coefficient between beta approximate to 0.5 . 10(21)s( -1) and beta approximate to 20 . 10(21)s(-1) have been deduced from previou s experiments. A new experimental access to the dynamics of fission is give n by peripheral nuclear collisions at relativistic energies. This method ha s important advantages with respect to the traditional ones, since highly e xcited nuclei are produced with low angular momenta and small shape distort ions. Preliminary results of applying this procedure at GSI Darmstadt are p resented.