Physical Review Accelerators and Beams (May 2019)
Quantum features of high energy particle incoherent scattering in crystals
Abstract
The coherent process of particle deflection by aligned atomic strings and planes of oriented crystals is accompanied by incoherent scattering by atomic cores. While the coherent particle deflection, described by the axial or planar averaged potential, becomes more and more classical at high energies, the incoherent scattering of relativistic particles remains essentially quantum. Though the incoherent scattering of relativistic particles in crystals reminds the scattering by atoms of an amorphous medium at a large momentum transfer, at small ones the incoherent scattering process in crystals is modified by the influence of the inhomogeneity of the atom distribution in the plane normal to the crystal axis or plane. We present a theory of incoherent scattering of high energy particles in oriented crystals, which takes into consideration both its quantum nature and the impact of the atom distribution inhomogeneity. The axial case is considered as a more general example. The way to incorporate the revealed quantum features into classical trajectory simulations is also outlined.