On the Generation of Phonons and Electronic Excitations by a Channeled Particle in Crystals

The processes of generating phonons and electronic excitations by an oriented quantum particle in a crystal are considered. The probabilities of the excitation of phonons and plasmons are calculated. A theory of crystal excitation by a channeled particle with simultaneous photon emission is developed. The probability of a process with the fast particle transitioning into a virtual state after emitting a plasmon, followed by photon emission, is determined. The probability of the process involving photon and plasmon emission is of the same order of magnitude as the probability of the standard process with photon emission alone. The possibility of experimentally detecting the effect is assessed. It is demonstrated that all features of electronic and phonon excitations manifest as components of the radiation spectrum from a fast oriented charged particle in a crystal.