Characteristics of quasi-synchrotron radiation of channeled electrons in crystals

The characteristics of channeled electron radiation in straight and curved crystals have been examined in order to find new ways for generation of electromagnetic radiation in the region of vacuum ultraviolet (VU). Under channeling a charged particle is moving in the averaged potential of an atomic string or plane with the transverse oscillations, which will result in electromagnetic radiation [1]. The radiation frequency is proportional in the hard spectral region to γ³ (γ being the Lorenz factor of electrons) owing to the Doppler effect and will be in the VU region already at electron energies of some MeV. The instantaneous intensity of the electron radiation in the crystal may exceed by a factor of 10⁵ the corresponding radiation intensity in synchrotrons. In curved channels the charged particles can be captured on the lattice-directed trajectories, the curvature radius of which is up to some R_min, with the efficiency N/N₀ = (1 - R_min/R). The value of R_min for E ≥ BeV attains some tenth parts of a centimeter. The characteristics of the electromagnetic radiation, which accompanies the movement of electrons in the curved crystals, were calculated [2]. The instantaneous power W = ( 2 3)e²β⁴c/R²(1 - β²)² at R = R_min and E {reversed tilde equals} 1 BeV exceeds by a factor of 10⁴ the corresponding value in synchrotrons. The spectral maximum of radiation in curved channels occurs at a frequency ω = ( 3 2)ω₀(1 - β²) ^{-3 2} where ω₀ = v/R, and at E ≥ 1 BeV, ω {reversed tilde equals} 10¹⁸ - 10²¹ s^-1, i.e., it will be in the VU or X-ray region.