Innovative approaches for Monte Carlo simulations of orientational effects in crystals and their experimental verification

Interaction of either charged or neutral particles with crystals is an area of science under development. Coherent effects of ultra‐relativistic particles in crystals allow manipulating particle trajectories thanks to the strong electrical field generated between atomic planes and axes. Coherent effects for interaction of particles with aligned structures always exploited opportunity furnished by the most advanced calculators and calculation methods of the current period. In this thesis two Monte Carlo codes were developed for the simulation of coherent interactions between charged particles and crystals. The Monte Carlo codes were tested for comparison with the experimental results of various experiments on channeling and related topics. The first code, named DYNECHARM++, is completely object‐oriented and deals with numerical integration of the equation of motion to determine the trajectory of a particle in straight and bent complex crystalline structures. The second code addresses the implementation of coherent effects, such as planar channeling and volume reflection to Geant4, which is a widespread used toolkit for the simulation of the passage of particles through matter. Experiments on coherent interactions were carried out at the H8 and H4 external lines of the SPS at CERN and at the MAMI of the Johannes Gutenberg University of Mainz. At the H8 line experiments of coherent interaction in "exotic" atomic structure and crystal configuration were worked out. Within the UA9 experiment, a procedure for the on‐beam characterization of the strips for the SPS crystal collimation experiment was developed at the H8 line. At the H4 line and at MAMI the interaction of negative particles with bent crystals was studied