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Scale-free Equilibria of Magnetized Polytropic Clouds

D. Galli·S. Lizano·Z. -Y. Li·F. C. Adams·F. H. Shu
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Abstract

We investigate the equilibrium properties of self-gravitating magnetized clouds with polytropic equations of state with negative index n. In particular, we consider scale-free isopedic configurations that have constant dimensionless spherical mass-to-flux ratio lambda_r and that may constitute ``pivotal'' states for subsequent dynamical collapse to form groups or clusters of stars. For given Gamma = 1 + 1/n, equilibria with smaller values of lambda_r are more flattened, ranging from spherical configurations with lambda_r = infinity to completely flattened states for lambda_r=1. For a given amount of support provided by the magnetic field as measured by the dimensionless parameter H_0, equilibria with smaller values of Gamma are more flattened. However, logatropic (defined by Gamma = 0) disks do not exist. The only possible scale-free isopedic equilibria with logatropic equation of state are spherical uniformly magnetized clouds.

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D. Galli, S. Lizano, Z. -Y. Li, F. C. Adams, F. H. Shu. 1999-04-02. Scale-free Equilibria of Magnetized Polytropic Clouds. https://doi.org/10.1086/307579

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