CONICET | Buscador de Institutos y Recursos Humanos

Fossil groups are considered old and virialized system, which have been assembled the largest fraction of their masses at high values of redshift. It is not expected that most of fossil groups show significant substructure, according to simulations and confirmed with radio observations. Nevertheless, some works find out from a sample of fossil groups a significant fraction of substructure, which is in agreement with non relaxed and virialized systems. In this work we study the probability of finding fossil groups merger candidates using a mock galaxies constructed on top of the Millennium Run Simulation I. We identifyfossil groups at redshift zero according to two different criteria, and analyse the merger history of these systems.