| Paper |
Title |
Page |
| THPC097 |
A Full Analytical Method to Determine Equilibrium Quantities of Mismatched Charged Particle Beams evolving in Linear Channels
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3203 |
| |
- R. P. Nunes, F. B. Rizzato
IF-UFRGS, Porto Alegre
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The focus of this work is to show a full analytical expression to determine relevant equilibrium quantities of a magnetically focused and high-intensity charged particle beam when evolving in a linear channel. Through the current approach, some intermediate steps of our original hybrid model which have to be solved numerically now can be eliminated, leading to the obtainment of a full analytical expression. This expression relates initial beam parameters with those obtained at equilibrium, allowing that the fraction of halo particles f can be evaluated. As a consequence, through the developed model, beam quantities like the envelope and emittance can be naturally determined. This is important in the accelerator engineering, since halo characteristics is a factor to be considered in the design of its confinement structure. For validation, full self-consistent N-particle beam numerical simulations have been carried out and its results compared with the predictions supplied by the full analytical model. The agreement is shown to be nice as with the simulations as with the hybrid numerical-analytical version of the model.
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| THPC098 |
Halo characterization of initially mismatched beams through phase-space modeling
|
3206 |
| |
- R. P. Nunes, F. B. Rizzato
IF-UFRGS, Porto Alegre
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This work discusses a method of characterizing the beam particles with just some assumptions about the entire beam phase-space topology. At equilibrium, the beam phase-space can be recognized as composed by almost two distinct regions: a thin horizontal branch over the r axis that is populated by the core particles and a curve branch in the dr/ds x r plane, which is populated by the halo particles. Since these regions have a regular shape, then it is readily possible to convert them to an analytical expression. Two distinct shapes have been employed (circular and elliptical) to model the beam halo branch. With this, all usual initial beam mismatch values are covered with accuracy to determine the beam envelope and emittance at equilibrium. Full self-consistent N-particle beam simulations have been carried out and its results compared with the ones obtained with the model. Results agreed nice for all analyzed mismatch cases.
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| THPC103 |
Wave Breaking and Test Particle Dynamics in Inhomogeneous Beams
|
3218 |
| |
- F. B. Rizzato, Y. Levin, R. P. Nunes, R. Pakter, E. G. Souza
IF-UFRGS, Porto Alegre
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This work analyzes the dynamics of inhomogeneous, magnetically focused high-intensity beams of charged particles. While for homogeneous beams the whole system oscillates with a single frequency, any inhomogeneity leads to propagating transverse density waves which eventually result in a singular density build up, causing wave breaking and jet formation. Wave breaking is shown to relax the mismatched beam and we make use of Lynden-Bell's theory of violent relaxation to estimate characteristics of the relaxed state.
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