Author: Ginzburg, N.S.
Paper Title Page
TUP016 Quasi-optical Theory of Terahertz Superradiance from an Extended Electron Bunch 391
 
  • N.S. Ginzburg, A. Malkin, A. Sergeev, V.Yu. Zaslavsky, I.V. Zotova
    IAP/RAS, Nizhny Novgorod, Russia
 
  Funding: This study was supported by the Russian Foundation for Basic Research (project no. 14-08-01180) and the Dynasty Foundation.
We consider superradiance of an extended relativistic electron bunch moving over a periodically corrugated surface for the generation of multi-megawatt terahertz pulses*. To study the above process we have developed a three-dimensional, self-consistent, quasi-optical theory of Cherenkov stimulated emission which includes a description of the formation of evanescent waves near the corrugated surface and its excitation by RF current induced in the electron bunch. Results obtained in the framework of a quasi-optical model were confirmed by direct CST STUDIO PIC simulations. There is a possibility of advancement towards still shorter wavelengths (infrared and optical), which can be achieved by decreasing the period of the diffraction gratings and increasing the density and energy of the particles in the electron bunches. Increase of coupling impedance can be obtained by using inclined incidence of electron bunch on corrugated surface (clinotron configuration).
Ginzburg N.S et al. Phys. Rev. Lett. 2013. V.110, Iss.18. 184801.
 
 
TUP017 Using Lorentz Transformations for Simulations of Wiggler Superradiance from the Picosecond Electron Bunches 395
 
  • A. Malkin, N.S. Ginzburg, A.A. Golovanov, I.V. Zotova
    IAP/RAS, Nizhny Novgorod, Russia
  • V.P. Tarakanov
    LPI, Moscow, Russia
 
  Funding: This work was supported by Russian Foundation for Basic Research under Grant No 12-02-01152.
In this paper we present a theoretical analysis of superradiance (SR) from picosecond electron bunches wiggling in periodical undulator field based both on the method of averaged ponderomotive force and on a direct numerical PIC (particle-in-cell) simulation. Within both approaches the analysis takes place in the reference frame co-moving with electrons which allows simplifying the procedure of simulation significantly due to the fact that all the spatial scales including the radiation wavelength, the length of the beam and the length of the pump field pacet into which the undulator field is transformed are of the same order. We show that in the reference frame the SR effect can be interpreted as a formation of the distributed Bragg mirror in the bulk of the electron beam which is effectively reflecting (scattering) the pump wave. A possibility of generation of multimegawatt pulses in terahertz and far infrared wave ranges is demonstrated.