In the hierarchical structure formation model cosmic halos are supposed to form by accretion of smaller units along anisotropic direction, defined by large-scale filamentary structures. After the epoch of primary mass aggregation (which depend on the cosmological model), violent relaxation processes will tend to alter the halo phase-space configuration producing quasi-spherical halos with a relatively smooth density profiles. Here we attempt to investigate the relation between halos shapes,

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... r environment and their dynamical state. To this end we have run a large (L=500 h^-1 Mpc, N_p=512^3 particles) N-body simulation of a flat low-density cold dark matter model with a matter density Ω_ m=1-Ω_Λ=0.3, Hubble constant H_∘=70 km s^-1 Mpc^-1 and a normalization parameter of σ_8=0.9. The particle mass is m_ p> 7.7× 10^10 h^-1 M_ comparable to the mass of one single galaxy. The halos are defined using a friends-of-friend algorithm with a linking length given by l=0.17ν̅ where ν̅ is the mean density. This linking length corresponds to an overdensity ρ/ρ_ mean≃ 200 at the present epoch (z=0) and the total number of halos with more than 130 particles (M>3 × 10^13 h^-1 M_) is 57524.