Spectroscopy of the radiation emitted by channeled particles—a new method of study of crystals

Bethe-Salpeter equation for the description of electron channeling

“…The resulting considerable simplification of the problem is very important for application purposes such as crystal diagnostics by using channeling radiation spectra. 6 A feed-up effect in thick crystals can be described by a coherence function or density matrix in coordinate representation Tz(z, rll, r,,) = (V(z, r L l ) . v*(z, r12)) which satisfies an equation analogous to the BetheSalpeter equation (subscripts I will be further omitted) a az 2ikZ -r2@, r,, 2 2 ) …”

“…Inserting(6) into Eq. (2) and multiplying by the complex conjugate to (6) one finds after integration over the channel cross area with regard of the orthogonality of eigenfunctions or where is the scattering (imaginary) part of the crystal potential due to incoherent elastic scattering by the atomic nuclei.…”

Measurement of Planar Channeling Radiation from 19.2 MeV Electrons in Silicon Using a Microtron

“…Recently in a number of experimental and theoretical studies a possibility of using channeling radiation [l] for diagnosing the properties of crystals [2,3] has been demonstrated. Measuring relativistic electron channeling radiation in single crystals [4 to 91 may become a new instrument for determining the concentration of defects and impurities, crystal potentials, and other characteristics of elementary and complex crystalline structures.…”