WED07
MEPhI, Moscow, Russia
NRC, Moscow, Russia
BNRU, Belgorod, Russia
Smith-Purcell radiation (SPR) is generated when an electron beam passes near a diffraction grating. Contrary to other methods (scintillator and transition radiation screens, wire scanners, etc.) SPR is not accompanied by the scattering of the beam¿s electrons on the target. This unique feature lets SPR provide non-destructive diagnostics of relativistic electron beams in linacs, including single shot measurements. Beam diagnostics is carried out by comparing experimental data with theoretical ones* and the following extraction of the beam parameters. Existing theoretical models are valid in the wave zone (but for the only exception of qualitative estimates in **), i.e. the detector must be placed at the distances much more than the wavelength of radiation multiplied by gamma2, where gamma is the Lorentz factor of the electrons. For ultrarelativistic beams (e.g., gamma = 100) the wave zone starts from 10 meters or more for the wavelength in mm and sub-mm ranges, which is completely out of realistic experimental conditions. Therefore, theory in prewave zone is needed. In this paper we solve this problem, developing the results published recently in ***. We analyze the radiation characteristics and also discuss how to use the results for the relativistic beam diagnostics.
*H.L. Andrews, et al., Phys. Rev. STAB 17, 052802 (2014).
**D.V. Karlovets, A.P. Potylitsyn, JETP Letters 84, 579 (2006).
***D.I. Garaev, et al., Phys. Rev. B 103, 075403 (2021).
