All-atom relativistic molecular dynamics simulations of channeling and radiation processes in oriented crystals

We review achievements made in recent years in the field of numerical modeling of ultra-relativistic projectiles propagation in oriented crystals, radiation emission and related phenomena. This topic is highly relevant to the problem of designing novel gamma-ray light sources based on the exposure of oriented crystals to the beams of ultra-relativistic charged particles. The paper focuses on the approaches that allow for advanced computation exploration beyond the continuous potential and the binary collisions frameworks. A comprehensive description of the multiscale all-atom relativistic molecular dynamics approach implemented in the MBN Explorer package is given. Several case studies related to modeling of ultra-relativistic projectiles (electrons, positron and pions) channeling and photon emission in oriented straight, bent and periodically bent crystals are presented. In most cases, the input data used in the simulations, such as crystal orientation and thickness, the bending radii, periods and amplitudes, as well as the energies of the projectiles, have been chosen to match the parameters used in the accomplished and the ongoing experiments. Wherever available the results of calculations are compared with the experimental data and/or the data obtained by other numerical means.