SASE FEL Storage Ring

We explore the possibility of operating a self-amplified spontaneous emission free electron laser with a storage ring. We use a semi-analytical model to obtain the evolution inside the undulator, by taking into account the interplay on the laser dynamics due to the induced energy spread and the radiation damping. We obtain the Renieri's limit for the stationary output power, and discuss the possibility of including in our model the effect of the beam instabilities.