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Self-consistent models of cuspy triaxial galaxies with dark matter haloes

R. Capuzzo-Dolcetta·L. Leccese·D. Merritt·A. Vicari
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Abstract

We have constructed realistic, self-consistent models of triaxial elliptical galaxies embedded in triaxial dark matter haloes. We examined three different models for the shape of the dark matter halo: (i) the same axis ratios as the luminous matter (0.7:0.86:1); (ii) a more prolate shape (0.5:0.66:1); (iii) a more oblate shape (0.7:0.93:1). The models were obtained by means of the standard orbital superposition technique introduced by Schwarzschild. Self-consistent solutions were found in each of the three cases. Chaotic orbits were found to be important in all of the models,and their presence was shown to imply a possible slow evolution of the shapes of the haloes. Our results demonstrate for the first time that triaxial dark matter haloes can co-exist with triaxial galaxies.

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R. Capuzzo-Dolcetta, L. Leccese, D. Merritt, A. Vicari. 2006-11-07. Self-consistent models of cuspy triaxial galaxies with dark matter haloes. https://doi.org/10.1086/519300

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