Simulations of a ring resonator free-electron laser

Journal Article · Sun Jan 01 04:00:00 EST 1989 · IEEE J. Quant. Electron.; (United States)

DOI:https://doi.org/10.1109/3.16243· OSTI ID:6547004

Tokar, R L; McVey, B D; Thode, L E ^[1]; Gallatin, G M ^[2]

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1. Los Alamos National Lab., Los Alamos, NM (US)
2. Research Dept., The Perkin-Elmer Corp., Danbury, CT (US)

In this paper, a relatively high gain (approx. = 25 to 40 percent) free-electron laser (FEL) with an optical ring resonator is simulated using the code FELEX. The laser system corresponds to the ''burst mode'' FEL scheduled for operation at Boeing Aerospace Company in 1988. The ring consists of paraboloids, grazing incidence by hyperboloids, and a grating rhomb. The wiggler is 5 m in length and has an adjustable taper, while the electron beam is produced by an RF linac. The optical elements of the ring together with the FEL interaction in the wiggler are modeled in three spatial dimensions to investigate the system from start-up to saturation. Both single frequency and finite pulse simulations are performed. The study illustrates the necessity of mode matching the loaded resonator to maximize the extraction efficiency. The mode matching is necessary because the FEL interaction significantly alters the optical beam focus position and Rayleigh range. The mode-matching procedure adopted is to vary the radii of curvature of the paraboids to achieve an optical mode that resembles the lowest order Gaussian mode of the unloaded cavity. In addition, the study illustrates that the dispersion provided by the grating rhomb further increases the extraction efficiency because it improves the overlap of the optical and electron pulse. This result is consistent with one-dimensional pulse simulations for this system.

• OSTI ID: 6547004
• Journal Information: IEEE J. Quant. Electron.; (United States), Journal Name: IEEE J. Quant. Electron.; (United States) Vol. 25:1; ISSN IEJQA
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
420300* -- Engineering-- Lasers-- (-1989)
43 PARTICLE ACCELERATORS
430200 -- Particle Accelerators-- Beam Dynamics
Field Calculations
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ACCELERATORS
AMPLIFICATION
BEAMS
COLLECTIVE ACCELERATORS
COMPUTER CODES
ELECTRON BEAMS
ELECTRON-RING ACCELERATORS
F CODES
FREE ELECTRON LASERS
GAIN
LASERS
LEPTON BEAMS
PARTICLE BEAMS
SIMULATION
STORAGE RINGS