Electron orbits in free-electron lasers with helical wiggler and axial guide magnetif fields

Journal Article · Mon Jul 01 04:00:00 EDT 1985 · IEEE J. Quant. Electron.; (United States)

DOI:https://doi.org/10.1109/JQE.1985.1072758· OSTI ID:5950659

Freund, H P; Ganguly, A K

An analytic theory of nonsteady-state trajectories in a fully three-dimensional, helical wiggler magnetic field is developed. In contrast to the well-known class of helical steady-state orbits, these orbits are not axicentered. Two limiting cases are considered. In the case of trajectories which are axis-encircling, we obtain a class of orbits by perturbation about the steady-state limit. We also consider the opposite regime in which particle trajectories are not axis-encircling, and derive a guiding-center theory for the limiting case in which the particles remain far from the axis of symmetry. In both limits we obtain trajectories which consist of periodic motions corresponding to both the fast wiggler and Larmor periods, as well as a slow motion corresponding to betatron oscillations arising from the transverse inhomogeneity in the wiggler field.

• Research Organization: Naval Research Laboratory, Washington, DC
• OSTI ID: 5950659
• Journal Information: IEEE J. Quant. Electron.; (United States), Journal Name: IEEE J. Quant. Electron.; (United States) Vol. GE-21:7; ISSN IEJQA
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
420300* -- Engineering-- Lasers-- (-1989)
BEAM DYNAMICS
BETATRON OSCILLATIONS
BOUNDARY CONDITIONS
ELECTRICAL EQUIPMENT
ELECTROMAGNETS
ELECTRONS
ELEMENTARY PARTICLES
EQUIPMENT
FERMIONS
FREE ELECTRON LASERS
GUIDING-CENTER APPROXIMATION
INHOMOGENEOUS FIELDS
LARMOR RADIUS
LASERS
LEPTONS
LIMITING VALUES
MAGNETIC FIELDS
MAGNETS
ORBITS
OSCILLATIONS
STEADY-STATE CONDITIONS
TRAJECTORIES
WIGGLER MAGNETS