Stimulated Radiation of Particles in Crystallic Undulators

It is investigated the stimulated radiation which arises when the density and energy of the beam of relativistic particles channeled in microscopic crystallic undulators (CU) obtained by the application of transverse ultrasonic (US) oscillations to single crystals, exceed certain values. For positron beams expected at future linear colliders and real CU it is given the results of numerical calculations for spontaneous and stimulated radiation.