STATISTICS OF MASS AGGREGATION IN A SELF-GRAVITATING ONE-DIMENSIONAL GAS

We study at the microscopic level the dynamics of a one-dimensional, g ravitationally interacting sticky gas. Initially, N identical particle s of mass m with uncorrelated, randomly distributed Velocities fill ho mogeneously a finite region of space. It is proved that at a character istic time a single macroscopic mass is formed with certainty, surroun ded by a dust of nonextensive fragments. In the continuum limit this c orresponds to a single shock creating a singular mass density. The sta tistics of the remaining fragments obeys the Poisson law at all times following the shock. Numerical simulations indicate that up to the mom ent of macroscopic aggregation the system remains internally homogeneo us. At the short time scale a rapid decrease in the kinetic energy is observed, accompanied by the formation of a number similar to root N o f aggregates with masses similar to m root N.