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arXiv · astro-ph/9907417

Formation of Elliptical and S0 Galaxies by Close Encounters

Thorsten Naab·Andreas Burkert
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Abstract

We study a possible formation mechanism for elliptical/S0 galaxies using N-body simulations with GRAPE. A close galaxy encounter which does not lead to a merger can induce a strong bar in an initially axisymmetric disk. This bar is unstable against bending oscillations and loses angular momentum to the dark halo. After 6 Gyrs the remnant is spheroidal with a de Vaucouleurs-type surface profile and has ellipticities and rotation properties comparable to observed elliptical/S0 galaxies: the system rotates fast (v/sigma \approx 1) and has disky isophotes.

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Thorsten Naab, Andreas Burkert. 1999-07-29. Formation of Elliptical and S0 Galaxies by Close Encounters. https://arxiv.org/abs/astro-ph/9907417

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