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Fluctuations Do Matter: Large Noise-Enhanced Halos in Charged-Particle Beams

Courtlandt L. Bohn·Ioannis V. Sideris
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Abstract

The formation of beam halos has customarily been described in terms of a particle-core model in which the space-charge field of the oscillating core drives particles to large amplitudes. This model involves parametric resonance and predicts a hard upper bound to the orbital amplitude of the halo particles. We show that the presence of colored noise due to space-charge fluctuations and/or machine imperfections can eject particles to much larger amplitudes than would be inferred from parametric resonance alone.

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Courtlandt L. Bohn, Ioannis V. Sideris. 2003-05-31. Fluctuations Do Matter: Large Noise-Enhanced Halos in Charged-Particle Beams. https://doi.org/10.1103/physrevlett.91.264801

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