Mean field escapers in non-equilibrium systems

We present some results of our study on non-equilibriumN-body systems that undergo initial collapse. This collapse is followed by global pulsations of the system. During these pulsations, the mean gravitational field fluctuates violently. Some particles pick up enough energy to be ejected from the system into the halo or even fly off to infinity. We discuss the region in phase space from which these mean field escapers originate and their energy frequency distribution for the illustrative case of a uniform spherical initial state. The pulsations lead to the production of shells in the halo.Paper presented at the 11th European Regional Astronomical Meetings of the IAU on New Windows to the Universe, held 3–8 July, 1989, Tenerife, Canary Islands, Spain.