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The Temperature Distribution in Turbulent Interstellar Gas

A. Gazol·E. Vazquez-Semadeni·F. J. Sanchez-Salcedo·J. Scalo
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Abstract

We discuss the temperature distribution in a two-dimensional, thermally unstable numerical simulation of the warm and cold gas in the Galactic disk, including the magnetic field, self-gravity, the Coriolis force, stellar energy injection and a realistic cooling function. We find that ~50% of the turbulent gas mass has temperatures in what would be the thermally unstable range if thermal instability were to be considered alone. This appears to be a consequence of there being many other forces at play than just thermal pressure. We also point out that a bimodal temperature pdf is a simple consequence of the form of the interstellar cooling function and is not necessarily a signature of discontinuous phase transitions.

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A. Gazol, E. Vazquez-Semadeni, F. J. Sanchez-Salcedo, J. Scalo. 2001-05-23. The Temperature Distribution in Turbulent Interstellar Gas. https://doi.org/10.1086/322873

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