Long-term evolution of initially unvirialized, clumpy, mass-segregated star clusters in tidal fields

Star clusters can form in highly substructured configurations, possibly unvirialized and possibly with a primordial degree of mass segregation. None the less, a common assumption of many N-body simulations of star clusters is that the clusters are initially spherical, homogeneous and in virial equilibrium. The impact of the choice of the initial conditions on the long-term evolution of the clusters is unclear, considering also that the tidal field plays an important role in setting the mass-loss rate and size of dynamically evolved objects. We present a series direct N-body simulations of star clusters spanning a range of initial degree of clumpiness, virial state and mass segregation and following different trajectories in a realistic galactic tidal field. The results suggest that, even if the choice of the initial conditions has a non-negligible impact, the long-term evolution of a star cluster seems to be dominated by the tidal forces experienced along its trajectory in the host galaxy.