Development of a Waveguide FEL Seeded in the 1-3 THz Range for Microbunching Experiment at the Neptune Laboratory

Journal Article · Mon Nov 27 04:00:00 EST 2006 · AIP Conference Proceedings

DOI:https://doi.org/10.1063/1.2409231· OSTI ID:20898772

Sung, C; Tochitsky, S Ya; Reiche, S; Rosenzweig, J B; Pellegrini, C; Joshi, C ^[1]; Gottschalk, S C; Kimura, W D ^[2]

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1. Neptune Laboratory, Departments of Electrical Engineering and Physics, University of California, Los Angeles, CA 90095 (United States)
2. STI Optronics, Inc., Bellevue, WA 98004-1495 (United States)

IFEL and FEL techniques can be used to modulate an electron beam on the scale of the radiation wavelength. However, the lack of a high power radiation source in the 100-300 {mu}m range hinders the progress on THz IFEL microbunching. In this paper, we discuss microbunching of an electron beam using a single-pass FEL seeded with a low power THz pulse generated by frequency mixing of CO2 laser lines in a GaAs nonlinear crystal. A narrowband THz seed source is pumped by a dual beam TEA CO2 laser and can be tuned in the 1-3 THz range. The THz radiation is guided through a hollow waveguide inside the planar FEL undulator driven by a photoinjector. By using a time-dependent FEL code GENESIS 1.3, we optimized the undulator parameters and analyzed the dynamics of the modulated electron beam. By using a {approx} 8 MeV electron beam with a peak current of 40 A and a {approx}1kW THz seed with wavelength 200 {mu}m, the energy modulation up to 1.3% can be achieved in a {approx}1.8-m long undulator with a constant period of 2.7 cm. At present, the THz seed source is built and fully characterized. The results of transmission measurements for THz waveguides are also discussed.

• OSTI ID: 20898772
• Journal Information: AIP Conference Proceedings, Journal Name: AIP Conference Proceedings Journal Issue: 1 Vol. 877; ISSN APCPCS; ISSN 0094-243X
• Country of Publication: United States
• Language: English

Related Subjects

43 PARTICLE ACCELERATORS
BEAM BUNCHING
CARBON DIOXIDE LASERS
CRYSTALS
ELECTRON BEAMS
FREE ELECTRON LASERS
FREQUENCY MIXING
GALLIUM ARSENIDES
MEV RANGE 01-10
MODULATION
NONLINEAR PROBLEMS
PULSES
RADIATION SOURCES
THZ RANGE 01-100
TIME DEPENDENCE
WAVEGUIDES
WAVELENGTHS
WIGGLER MAGNETS