The problem and influence of coherency effects on motion of charged particles in perfect oriented crystals
Kiev National Shevchenko University
Last modified: April 25, 2006
The problem of mutual coherency in space and time of moving material bodies is one of the most interesting in modern physics. This effect has no analogs in classical physics.
In the work the length of reciprocal coherency existence and peculiarities of coherency of different states of channeled charged particles wave functions are discussed. It was shown that the length of coherent channeling at the beginning of crystal target (immediately behind an entering surface of a crystal) depends on the monochromaticity of initial particle beam as well as from the interaction of channeled particles with thermal oscillations of the crystal lattice. The length of coherent channeling can vary from 1 micrometer for low energy particles (nonrelativistic ions and low relativistic electrons and positrons) to more then 10-20 micrometers for ultrarelativistic particles.
Peculiarities of influence of coherency processes at relativistic and nonrelativistic charged particles channeling on spatial and angular characteristics of particle beam that has passed through the thin crystal are also discussed. In was shown that the influence of different particle states interference within the area of coherent channeling leads to very strong periodic dependence of final beam angular width from the crystal length. This effect allows to control beam parameters (e.g. to form narrower beam, that it was before falling on the crystal). It was shown that the process of decreasing of angular divergence at coherent channeling in perfect crystal does not contradict the theorem of phase volume conservation.
The influence of coherency of particle states in a single channel and several channels on the angular distribution and the possibility of controlled quasicharacteristic short-wave spontaneous and stimulated gamma-radiation is also studied.