  We study the density profiles of collapsed galaxy-size dark matter halos with
masses 1e11-5e12 Msun focusing mostly on the halo outer regions from the formal
virial radius Rvir up to 5-7Rvir. We find that isolated halos in this mass
range extend well beyond Rvir exhibiting all properties of virialized objects
up to 2-3Rvir: relatively smooth density profiles and no systematic infall
velocities. The dark matter halos in this mass range do not grow as one naively
may expect through a steady accretion of satellites, i.e., on average there is
no mass infall. This is strikingly different from more massive halos, which
have large infall velocities outside of the virial radius. We provide accurate
fit for the density profile of these galaxy-size halos. For a wide range
(0.01-2)Rvir of radii the halo density profiles are fit with the approximation
rho=rho_s exp(-2n[x^{1/n}-1])+rho_m, where x=r/r_s, rho_m is the mean matter
density of the Universe, and the index n is in the range n=6-7.5. These
profiles do not show a sudden change of behavior beyond the virial radius. For
larger radii we combine the statistics of the initial fluctuations with the
spherical collapse model to obtain predictions for the mean and most probable
density profiles for halos of several masses. The model give excellent results
beyond 2-3 formal virial radii.
