On the evolution and gravitational collapse of a toroidal vortex

The evolution and collapse of a gaseous toroidal vortex under the action of self-gravitation are considered using the Hamiltonian mechanics approach. It is shown that evolution occurs in three main stages separated by characteristic time scales. First, a compression along the small radius to a quasi-equilibrium state takes place, followed by a slower compression along the large radius to a more stable compact vortex object. In the latter stage, the possibility of effective scattering and ejection of particles along the vortex axis (jet formation) is detected. As a result, mass, energy, and momentum losses take place, and the vortex collapses. (C) 2003 MAIK "Nauka/Interperiodica".