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Title: Detecting chaos in particle accelerators through the frequency map analysis method

Abstract

The motion of beams in particle accelerators is dominated by a plethora of non-linear effects, which can enhance chaotic motion and limit their performance. The application of advanced non-linear dynamics methods for detecting and correcting these effects and thereby increasing the region of beam stability plays an essential role during the accelerator design phase but also their operation. After describing the nature of non-linear effects and their impact on performance parameters of different particle accelerator categories, the theory of non-linear particle motion is outlined. The recent developments on the methods employed for the analysis of chaotic beam motion are detailed. In particular, the ability of the frequency map analysis method to detect chaotic motion and guide the correction of non-linear effects is demonstrated in particle tracking simulations but also experimental data.

Authors:
 [1]
  1. European Organisation of Nuclear Research—CERN, Geneva (Switzerland)
Publication Date:
OSTI Identifier:
22351023
Resource Type:
Journal Article
Resource Relation:
Journal Name: Chaos (Woodbury, N. Y.); Journal Volume: 24; Journal Issue: 2; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ACCELERATORS; CHAOS THEORY; DESIGN; NONLINEAR PROBLEMS; PARTICLE BEAMS; PERFORMANCE

Citation Formats

Papaphilippou, Yannis, E-mail: Ioannis.Papaphilippou@cern.ch. Detecting chaos in particle accelerators through the frequency map analysis method. United States: N. p., 2014. Web. doi:10.1063/1.4884495.
Papaphilippou, Yannis, E-mail: Ioannis.Papaphilippou@cern.ch. Detecting chaos in particle accelerators through the frequency map analysis method. United States. doi:10.1063/1.4884495.
Papaphilippou, Yannis, E-mail: Ioannis.Papaphilippou@cern.ch. Sun . "Detecting chaos in particle accelerators through the frequency map analysis method". United States. doi:10.1063/1.4884495.
@article{osti_22351023,
title = {Detecting chaos in particle accelerators through the frequency map analysis method},
author = {Papaphilippou, Yannis, E-mail: Ioannis.Papaphilippou@cern.ch},
abstractNote = {The motion of beams in particle accelerators is dominated by a plethora of non-linear effects, which can enhance chaotic motion and limit their performance. The application of advanced non-linear dynamics methods for detecting and correcting these effects and thereby increasing the region of beam stability plays an essential role during the accelerator design phase but also their operation. After describing the nature of non-linear effects and their impact on performance parameters of different particle accelerator categories, the theory of non-linear particle motion is outlined. The recent developments on the methods employed for the analysis of chaotic beam motion are detailed. In particular, the ability of the frequency map analysis method to detect chaotic motion and guide the correction of non-linear effects is demonstrated in particle tracking simulations but also experimental data.},
doi = {10.1063/1.4884495},
journal = {Chaos (Woodbury, N. Y.)},
number = 2,
volume = 24,
place = {United States},
year = {Sun Jun 01 00:00:00 EDT 2014},
month = {Sun Jun 01 00:00:00 EDT 2014}
}
  • No abstract prepared.
  • Frequency map analysis was first used for the dynamical study of numerical simulations of physical systems (solar system, galaxies, particle accelerators). Here it is applied directly to the experimental results obtained at the Advanced Light Source. For the first time, the network of coupling resonances is clearly visible in an experiment, in a similar way as in the numerical simulation. Excellent agreement between numerical and experimental results leads us to propose this technique as a tool for improving numerical models and actual behavior of particle accelerators. Moreover, it provides a model-independent diagnostic for the evaluation of the dynamical properties ofmore » the beam. (c) 2000 The American Physical Society.« less
  • We describe the Pathway Analysis Through Habitat (PATH) tool, which can predict the location of potential corridors of animal movement between patches of habitat within any map. The algorithm works by launching virtual entities that we call 'walkers' from each patch of habitat in the map, simulating their travel as they journey through land cover types in the intervening matrix, and finally arrive at a different habitat 'island.' Each walker is imbued with a set of user-specified habitat preferences that make its walking behavior resemble a particular animal species. Because the tool operates in parallel on a supercomputer, large numbersmore » of walkers can be efficiently simulated. The importance of each habitat patch as a source or a sink for a species is calculated, consistent with existing concepts in the metapopulation literature. The manipulation of a series of contrived artificial landscapes demonstrates that the location of potential dispersal corridors and relative source and sink importance among patches can be purposefully altered in expected ways. Finally, potential dispersal corridors are predicted among remnant woodlots within three actual landscape maps.« less
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  • Frequency analysis is used to chart the global phase space structure for the most general case of an electron bound by Coulombic and harmonic potentials and perturbed by tilted electric and magnetic fields. Distinct order-chaos transitions are found together with an example of a wave function scarred by a 3D {open_quotes}exotic{close_quote}{close_quote} periodic orbit, thereby providing compelling evidence for the power of frequency analysis in studying multidimensional chaos. {copyright} {ital 1997} {ital The American Physical Society}