Author: Malkin, A.
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.