Js. Yu et al., ELECTRON ORBIT IN A COMBINED PLASMA-WAVE WIGGLER AND AN AXIAL GUIDE MAGNETIC-FIELD FREE-ELECTRON LASER NEAR MAGNETORESONANCE, IEEE transactions on plasma science, 21(1), 1993, pp. 167-169
The nonlinear electron orbit dynamics is presented for a combined elec
trostatic plasma wave wiggler and an axial guide magnetic field free e
lectron laser near magnetoresonance. The perpendicular orbit equation
is derived and simplified identical to the wave-driven nonlinear oscil
lator equation [8] but with different expressions of parameters. The n
onlinear effect induced by the inclusion of beta(perpendicular-to)2 in
the relativistic factor gamma is dominant in governing the perpendicu
lar wiggling velocity and the orbit excursion even in the case of beta
(perpendicular-to)2 much less than beta(parallel-to)2, where gamma = (
1 - beta(perpendicular-to)2-beta(parallel-to)2-1/2. The dependence of
the maximum perpendicular wiggling velocity and the orbit excursion of
the wiggler constant. the wiggler frequency, and the initial paramete
rs of motion is given analytically.