Cooperative light scattering by a cold atomic fluid

We review some recent results on cooperative light scattering by clouds of cold two-level atoms driven by a resonant laser beam. In the linear regime, the atomic local response is described by an integro-differential fluid equation which accounts for the absorption and spontaneous emission processes. Cooperativity manifests itself as the re-emitted radiation creates correlations between atoms. The scattering pattern and the radiation pressure force acting on the cloud have been calculated at different levels of approximation, since they may easily be measured in experiments with cold and ultra-cold atoms.