Single-particle analysis of the free-electron laser sideband instability for primary electromagnetic wave with constant phase and slowly varying phase
Use is made of the single-particle orbit equations together with Maxwell's equations and appropriate statistical averages to investigate detailed properties of the sideband instability for a helical-wiggler free-electron laser with wiggler wavelength lambda/sub 0/ = 2..pi../k/sub 0/ = const and normalized wiggler amplitude a/sub w/ = eB-italic-circumflex/sub w//mc/sup 2/k/sub 0/ = const. The model describes the nonlinear evolution of a right-circularly polarized primary electromagnetic wave with frequency ..omega../sub s/, wavenumber k/sub s/, and slowly varying amplitude a-italic-circumflex/sub s/(z,t) and phase delta/sub s/(z,t) (eikonal approximation). The orbit and wave equations are analyzed in the ponderomotive frame (''primed'' variables) moving with velocity v/sub p/ = ..omega../sub s//(k/sub s/+k/sub 0/) relative to the laboratory. Detailed properties of the sideband instability are investigated for small-amplitude perturbations about a quasisteady equilibrium state characterized by a-italic-circumflex/sup 0//sub s/ = const (independent of z' and t'). Two cases are treated. The first case assumes constant equilibrium wave phase delta/sup 0//sub s/ = const, which requires (for self-consistency) both untrapped- and trapped-electron populations satisfying = 0.
- Research Organization:
- Science Applications International Corporation, Boulder, Colorado 80302
- OSTI ID:
- 6868165
- Journal Information:
- Phys. Fluids; (United States), Journal Name: Phys. Fluids; (United States) Vol. 30:2; ISSN PFLDA
- Country of Publication:
- United States
- Language:
- English
Similar Records
Influence of the trapped-electron distribution on the sideband instability in a helical wiggler free-electron laser
Kinetic description of the sideband instability in a helical-wiggler free-electron laser
Related Subjects
420300* -- Engineering-- Lasers-- (-1989)
DIFFERENTIAL EQUATIONS
ELECTRICAL EQUIPMENT
ELECTROMAGNETIC RADIATION
ELECTROMAGNETS
EQUATIONS
EQUIPMENT
FREE ELECTRON LASERS
INSTABILITY
LASERS
MAGNETS
MATHEMATICS
MAXWELL EQUATIONS
PARTIAL DIFFERENTIAL EQUATIONS
RADIATIONS
STATISTICS
TRAJECTORIES
WIGGLER MAGNETS