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Stabilizing the intensity of a wave amplified by a beam of particles

Romain Bachelard·Andrea Antoniazzi·Cristel Chandre·Duccio Fanelli·Xavier Leoncini·Michel Vittot
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Abstract

The intensity of an electromagnetic wave interacting self-consistently with a beam of charged particles as in a free electron laser, displays large oscillations due to an aggregate of particles, called the macro-particle. In this article, we propose a strategy to stabilize the intensity by re-shaping the macro-particle. This strategy involves the study of the linear stability (using the residue method) of selected periodic orbits of a mean-field model. As parameters of an additional perturbation are varied, bifurcations occur in the system which have drastic effect on the modification of the self-consistent dynamics, and in particular, of the macro-particle. We show how to obtain an appropriate tuning of the parameters which is able to strongly decrease the oscillations of the intensity without reducing its mean-value.

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Romain Bachelard, Andrea Antoniazzi, Cristel Chandre, Duccio Fanelli, Xavier Leoncini, Michel Vittot. 2006-09-12. Stabilizing the intensity of a wave amplified by a beam of particles. https://doi.org/10.1140/epjd%2Fe2006-00276-x

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