Large Fluctuations and Dynamic Phase Transition in a System of Self-Propelled Particles

We study the statistics, in stationary conditions, of the work WÏ\u84 done by the active force in different systems of self-propelled particles in a time Ï\u84. We show the existence of a critical value WÏ\u84â\u80  such that fluctuations with WÏ\u84>WÏ\u84â\u80  correspond to configurations where interaction between particles plays a minor role whereas those with WÏ\u8