Scaling Laws in Self-Gravitating Disks
نویسندگان
چکیده
Abstract. The interstellar medium (ISM) reveals strongly inhomogeneous structures at every scale. These structures do not seem completely random since they obey certain power laws. Larson’s law (1981) σ ∝ R and the plausible assumption of virial equilibrium justify to consider fractals as a possible description of the ISM. In the following we investigate how self-gravitation, differential rotation and dissipation affect the matter distribution in galaxies. To this end we have performed 3Dsimulations for self-gravitating local boxes embedded in a larger disk, extending the 2D-method of Toomre & Kalnajs (1991) and Wisdom & Tremaine (1988). Our simulations lead to the conclusion that gravitation, shearing and dissipation can be dominantly responsible for maintaining an inhomogeneous and eventually a fractal distribution of the matter.
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