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Turbulent dissipation in the interstellar medium: implications for galaxy formation and evolution

V. Avila-Reese·E. Vázquez-Semadeni
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Abstract

We study turbulent dissipation in the ISM and explore some implications for galaxy formation and evolution using 2D MHD numerical simulations of compressible fluids. The turbulent kinetic energy E_k is injected by stellar sources formed self-consistently in the simulation. In the ISM-like fluid, regimes of both forced and decaying turbulence coexist. In the active turbulent regions (forced regime), E_k is dissipated locally and efficiently. In the decaying regime (far from input sources), E_k(t) decays ~(1+t)^-0.8. The residual turbulent motions may propagate distances of the order of the observed disk height, suggesting that turbulence may be the responsible of vertical support and star formation self-regulation at the disk level, but not at the level of the whole cosmological halo, as would be required in some models of galaxy formation.

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V. Avila-Reese, E. Vázquez-Semadeni. 2000-04-26. Turbulent dissipation in the interstellar medium: implications for galaxy formation and evolution. https://arxiv.org/abs/astro-ph/9912062

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