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Global Spiral Modes in Star-Forming Gravitating Disks

Vladimir Korchagin·Christian Theis
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Abstract

Using 2D nonlinear simulations, we study the generation and nonlinear evolution of spiral structure in a star-forming multi-component gravitating disk. We confirm in agreement with previous studies the destabilizing role of a cold gaseous component and extend this conclusion for multi-component star-forming disks exchanging mass and momentum between its components. We show that the spiral structure growing on a non-stationary multi-phase background reaches its saturation in a similar manner like the one-component disks. The spiral structure survives even if most of the gas is transformed into stellar remnants of larger velocity dispersion.

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Vladimir Korchagin, Christian Theis. 1999-05-17. Global Spiral Modes in Star-Forming Gravitating Disks. https://arxiv.org/abs/astro-ph/9905219

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