CLASSICAL GLUON RADIATION ULTRARELATIVISTIC NUCLEAR COLLISIONS - SPACE-TIME STRUCTURE, INSTABILITIES, AND THERMALIZATION

We investigate the space-time structure of the classical gluon field p roduced in an ultrarelativistic collision between color charges. The c lassical solution which was computed previously in a perturbative appr oach is shown to become unstable on account of the non-Abelian self-in teraction neglected in the perturbative solution scheme. The time scal e for growth of the instabilities is found to be of the order of the d istance between the colliding color charges. We argue that these insta bilities will eventually lead to thermalization of gluons produced in an ultrarelativistic collision between heavy nuclei. The rate of therm alization is estimated to be of order g(2) mu, where g is the strong c oupling constant and mu(2) the transverse color charge density of an u ltrarelativistic nucleus.