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arXiv · 1009.3096

On the Interpretation of the l-v Features in the Milky Way Galaxy

Junichi Baba·Takayuki R. Saitoh·Keiichi Wada
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Abstract

We model the gas dynamics of barred galaxies using a three-dimensional, high-resolution, $N$-body+hydrodynamical simulation and apply it to the Milky Way in an attempt to reproduce both the large-scale structure and the clumpy morphology observed in Galactic H\emissiontype{I} and CO $l-v$ diagrams. Owing to including the multi-phase interstellar medium, self-gravity, star-formation and supernovae feedback, the clumpy morphology, as well as the large-scale features, in observed $l-v$ diagrams are naturally reproduced. We identify in our $l-v$ diagrams with a number of not only large-scale peculiar features such as the '3-kpc arm', '135-km s$^{-1}$ arm' and 'Connecting arm' but also clumpy features such as `Bania clumps', and then link these features in a face-on view of our model. We give suggestions on the real structure of the Milky Way and on the fate of gas clumps in the central region.

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Junichi Baba, Takayuki R. Saitoh, Keiichi Wada. 2010-09-16. On the Interpretation of the l-v Features in the Milky Way Galaxy. https://doi.org/10.1093/pasj%2F62.6.1413

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