Coherent radiation of atoms and a channeling particle
  New mechanism of radiation emitted at channeling of a relativistic particle in a crystal is studied. Superposition of coherent radiation of the atoms in a crystal lattice which are excited by a channeling particle and radiation of the channeling particle itself is considered. It is shown that coherent radiation of the chain of oscillating atoms forms a resonance peak on the background of radiation of the channeling particle. 
V. Epp and M. A. Sosedova
physics.acc-ph