On the theory of polarization radiation in media with sharp boundaries

    Research output: Contribution to journalArticle

    31 Citations (Scopus)

    Abstract

    Polarization radiation generated when a point charge moves uniformly along a straight line in vac- uum in the vicinity of media with a finite permittivity e(.) = e′ + ie′′ and sharp boundaries is considered. A method is developed in which polarization radiation is represented as the field of the current induced in the substance by the field of the moving charge. The solution to the problem of radiation induced when a charge moves along the axis of a cylindrical vacuum channel in a thin screen with a finite radius and a finite permit- tivity is obtained. Depending on the parameters of the problem, this solution describes various types of radi- ation (Cherenkov, transition, and diffraction radiation). In particular, when the channel radius tends to zero and the outer radius of the screen tends to infinity, the expression derived for the emitted energy coincides with the known solution for transition radiation in a plate. In another particular case of ideal conductivity (ε′′ → ∞), the relevant formula coincides with the known results for diffraction radiation from a circular aperture in an infinitely thin screen. The solution is obtained to the problem of radiation generated when the charge flies near a thin rectangular screen with a finite permittivity. This solution describes the diffraction and Cherenkov mechanisms of radiation and takes into account possible multiple re-reflections of radiation in the screen. The solution to the problem of radiation generated when a particles flies near a thin grating con- sisting of a finite number of strips having a rectangular cross section and a finite permittivity and separated by vacuum gaps (Smith-Purcell radiation) is also obtained. In the special case of ideal conductivity, the expres- sion derived for the emitted energy coincides with the known result in the model of surface currents.

    Original languageEnglish
    Pages (from-to)27-45
    Number of pages19
    JournalJournal of Experimental and Theoretical Physics
    Volume113
    Issue number1
    DOIs
    Publication statusPublished - Jul 2011

    ASJC Scopus subject areas

    • Physics and Astronomy(all)

    Fingerprint Dive into the research topics of 'On the theory of polarization radiation in media with sharp boundaries'. Together they form a unique fingerprint.

  • Cite this