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arXiv · astro-ph/9908162

Formation of Gaseous Shells

F. Combes·V. Charmandaris
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Abstract

HI observations have revealed in several shell galaxies the presence of gaseous shells slightly displaced from the stellar shells radially, in the outward direction. We propose a mechanism to form this gaseous shells, based on the well-known phase-wrapping process of the companion matter in a merger, with nearly radial orbits. The mechanism relies on the existence of a clumpy interstellar matter, and on dynamical friction experienced by the companion core.

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F. Combes, V. Charmandaris. 1999-08-16. Formation of Gaseous Shells. https://arxiv.org/abs/astro-ph/9908162

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