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DOE OSTI · 1600311

Method for energy dither of a particle beam

Powers, Thomas Joseph·Douglas, David R.·Evtushenko, Pavel·Benson, Stephen V.·Neil, George
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Abstract

A method for varying the wavelength of a free electron laser (FEL) by applying an energy dither to the charged particles supplying the FEL. Bunches of charged particle beams are accelerated by cavities that are operated at a harmonic of the bunch repetition rate. The method involves adding one or more secondary radiofrequency accelerator cavities after the primary beam transport and near the wiggler to apply a fluctuation between individual bunches with a pseudo-random distribution. The secondary radiofrequency accelerator cavities provide fine variations of the beam energy about a nominal operating point. Operating a free electron laser (FEL) with a 1% change in the electron beam energy via the added secondary cavities will result in a 2% wavelength variation of the FEL output.

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS

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Powers, Thomas Joseph, Douglas, David R., Evtushenko, Pavel, Benson, Stephen V., Neil, George. 2019-11-19. Method for energy dither of a particle beam. https://www.osti.gov/biblio/1600311

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