Hierarchical Friend-of-Friend algorithm to extract substructures from dark matter halos

MARIO AGUSTIN SGRÓ; ANDRES NICOLAS RUIZ; MANUEL MERCHÁN

Salta

Congreso; Reunion anual de la asociacion argentina de astronomia; 2010

IATE

We present a substructures identification algorithm able to extract local overdensities from dark matter halos in a cosmological N-body simulation. We start with a standard Friend-of-Friend (FoF) algorithm to obtain the dark matter halos from a given simulation output. The subsequent peaks of increasing density are then disjoined by decrea-sing recursively the link- ing lenght parameter, decomposing each halo into a principal subhalo plus minor overdensities within. In every identification level we analize each subhalo to remove all unbounded particles by applying an energy criterion. In this work we describe our algorithm and show some preliminar results.