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

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.

2 pages, 2 figures; to appear in the proceedings of the conference "Gas and Galaxy Evolution" (ASP Conference Series), eds. J. E. Hibbard, M. P. Rupen, and J. H. van Gorkom