BSMLSFMA · Beam Stability in Modern Light Sources via Frequency Map Analysis
FP6 — Marie Curie Actions (Human Resources and Mobility)
- Duration
- 2006-02-01 → 2008-01-31
- EU contribution
- €208,352
- Participants
- 1
- Scheme
- EIF
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Results in brief
Final Activity Report Summary - BSMLSFMA (Beam Stability in Modern Light Sources via Frequency Map Analysis)
The main objective of the project was the application of well-established methods of non-linear Hamiltonian dynamics, such as the frequency map analysis (FMA), in order to understand the beam stability properties in modern light sources in theory, simulations and experiments. To this end an efficient tracing code based on symplectic integration schemes was build, allowing the fast and accurate simulation of orbits of single particles in models of various real machines like the ESRF storage ring (Grenoble, France), and the Compact Linear Collider (CLIC) damping rings (CERN, Geneva, Switzerland). The acquired simulation data, as well as experimental measurements were analysed through FMA. In the case of experimental beam position measurements special attention was given to the problem of the decoherence of the beam, which diminishes drastically the number of turns for the tune determination, with data above the noise level. One of the main results of the project was that analysing data from equally spaced beam position monitors (BPMs) not having the same optics, or even from many BPMs that are not even equally spaced, a fast and accurate tune determination is obtained. The main source of nonlinear effects in beam dynamics is the presence of sextupoles. A basic outcome of our study is that the 'thin lense' approximation of sextupoles (i.e. the act of the sextupole is considered to be an instantaneous 'kick' of the beam), which is often used in dynamical studies of accelerator models, influences strongly the frequency maps, and thus it should be avoided when the understanding of nonlinear effects is needed. Another outcome of the project was the introduction and application of the generalised alignment index (GALI) method for the rapid detection of chaos, as well as for the determination of the dimensionality of regular motion in multi-dimensional Hamiltonian systems.
Data: CORDIS, © European Union
Project objective
Advanced non-linear dynamics methods such as the frequency map analysis have proved very efficient in improving the performance of modern accelerators. In particular, the correction of the inherent high chromaticity in extremely low emittance lattices in modern light sources necessitates high sextupole fields, which significantly reduce the dynamic aperture. In these cases, classical dynamics approaches based on leading order perturbation theory are insufficient. The purpose of this research project is to employ the power of recently developed methods of non-linear Hamiltonian dynamics in order to understand the beam stability limitations in modern light sources.The ultimate outcome will be to provide advanced solutions for correcting the detrimental effect o f the non-linearities thus increasing their dynamic aperture. The expertise gathered by the Astronomy and non-linear dynamics group of the IMCEE in applied non-linear dynamical systems provides an ideal environment for the implementation of the proposed research project. The link between theory, simulations and the operating performance of a real machine will be assured by the application of these methods in data retrieved from experiments performed in the ESRF storage ring. Dr. Skokos is a young scientist who already has a wide background and experience in non-linear dynamics by developing and applying new methods for the study of chaotic behaviour in Hamiltonian systems.In particular, he has introduced the SALI index as a tool of stability analysis, for the distinction of regular from chaotic motion in conservative dynamical systems of arbitrary dimension. This knowledge will be complemented by the collaboration with the team headed by Dr. Laskar who developed among others, the frequency map analysis method. Furthermore, this multi-disciplinary project will diversify Dr. Skokos expertise, giving him an opportunity to build his research profile in the state of the art" methods of accelerator dynamics research."
Original text from CORDIS.
Participants
- OBSERVATOIRE DE PARIS · PARISCoordinatorFrance
Links
Data: CORDIS, © European Union