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The Impact of External Tidal Fields on the ISM of Dwarf Spheroidals

Sergey Mashchenko·Claude Carignan
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Abstract

It was found that for three dwarf spheroidal galaxies - Sculptor, Tucana, and Cetus - there is a correspondence between the distribution of associated HI gas and the projected tidal axis direction. Numerical hydrodynamical simulations confirmed the following scenario: SN Ia explosions remove most of the interstellar medium beyond the tidal radius of the dwarf galaxy, with most of the mass being in clouds moving along the principal tidal axis.

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Sergey Mashchenko, Claude Carignan. 2000-09-06. The Impact of External Tidal Fields on the ISM of Dwarf Spheroidals. https://arxiv.org/abs/astro-ph/0009100

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