Structural properties of Dark Matter Halos

Abstract

Using the results of a high mass resolution ($256^3$ particles) N-body simulation of a cluster-forming region, we study the statistic ${\sigma }_v-M$ for low mass halos (${\rm M} < 10^{12} {\rm M}_{\sun}$), and we compare it with three theoretical models. At the final redshift halos are well described by the Truncated Isothermal Sphere model recently introduced by Shapiro, Iliev & Raga (1999). We speculate that this is a consequence of the action of tidal fields on galaxy formation within clusters.

6 pages, 3 figures. Minor typos corrected, conclusions unchanged. To appear in the proceedings of the Marseille IGRAP99 conference "Clustering at High Redshift"