Large-scale Gas Dynamics in the Milky Way

P. Englmaier; O. E. Gerhard; N. Bissantz

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arXiv · astro-ph/0308250

Large-scale Gas Dynamics in the Milky Way

P. Englmaier·O. E. Gerhard·N. Bissantz

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Abstract

We present new gas flow models for the Milky Way inside the solar circle. Using a mass model derived from the COBE/DIRBE maps and clump giant star counts, and using a parametric model for the spiral arm pattern in the disk, we calculate the gas flow and compare with 12CO observations. We find that models with 4 spiral arms fit the observations better then 2-armed models. We also find that models with separate pattern speeds for the bar and spiral arms can explain the gas flow in the bar corotation region better than single-pattern speed models.

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P. Englmaier, O. E. Gerhard, N. Bissantz. 2003-08-14. Large-scale Gas Dynamics in the Milky Way. https://arxiv.org/abs/astro-ph/0308250

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