Coherent infrared radiation from the ALS generated via femtosecond laser modulation of the electron beam
Interaction of an electron beam with a femtosecond laser pulse co-propagating through a wiggler at the ALS produces large modulation of the electron energies within a short {approx}100 fs slice of the electron bunch. Propagating around the storage ring, this bunch develops a longitudinal density perturbation due to the dispersion of electron trajectories. The length of the perturbation evolves with a distance from the wiggler but is much shorter than the electron bunch length. This perturbation causes the electron bunch to emit short pulses of temporally and spatially coherent infrared light which are automatically synchronized to the modulating laser. The intensity and spectra of the infrared light were measured in two storage ring locations for a nominal ALS lattice and for an experimental lattice with the higher momentum compaction factor. The onset of instability stimulated by laser e-beam interaction had been discovered. The infrared signal is now routinely used as a sensitive monitor for a fine tuning of the laser beam alignment during data accumulation in the experiments with femtosecond x-ray pulses.
- Research Organization:
- Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
- Sponsoring Organization:
- USDOE Director. Office of Science. Office of High Energy and Nuclear Physics. Division of High Energy Physics (US)
- DOE Contract Number:
- AC03-76SF00098
- OSTI ID:
- 836045
- Report Number(s):
- LBNL-55688; CBP Note - 572; R&D Project: 455301; TRN: US0500458
- Resource Relation:
- Conference: 9th Biennial European Particle Accelerator Conference, EPAC'04, Lucerne (CH), 07/05/2004--07/09/2004; Other Information: PBD: 1 Jul 2004
- Country of Publication:
- United States
- Language:
- English
Similar Records
An Optical Streaking Method for Measuring Femtosecond Electron Bunches
Tailored Terahertz Pulses from a Laser-Modulated Electron Beam