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Halo Formation in Spheroidal Bunches with Self-Consistent Stationary Distributions

A. V. Fedotov·R. L. Gluckstern·S. S. Kurennoy·R. D. Ryne
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Abstract

A new class of self-consistent 6-D phase space stationary distributions is constructed both analytically and numerically. The beam is then mismatched longitudinally and/or transversely, and we explore the beam stability and halo formation for the case of 3-D axisymmetric beam bunches using particle-in-cell simulations. We concentrate on beams with bunch length-to-width ratios varying from 1 to 5, which covers the typical range of the APT linac parameters. We find that the longitudinal halo forms first for comparable longitudinal and transverse mismatches. An interesting coupling phenomenon - a longitudinal or transverse halo is observed even for very small mismatches if the mismatch in the other plane is large - is discovered.

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A. V. Fedotov, R. L. Gluckstern, S. S. Kurennoy, R. D. Ryne. 1998-07-20. Halo Formation in Spheroidal Bunches with Self-Consistent Stationary Distributions. https://arxiv.org/abs/physics/9807030

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