Société Civile Synchrotron SOLEIL

Improvement of the understanding of non-linear beam dynamics effects in light sources

Trainee: Xavier Nuel Gavaldà
Supervisor: Laurent Nadolski

The goal of this project is to optimize the linear and non-linear beam dynamics in order to explore all possible optical settings available for the current accelerator lattice of the SOLEIL storage ring.

Dynamical Aperture 

Initially this project is to collect basic literature and explore the application of tracking codes (BETA and ELEGANT) using the SOLEIL computer cluster. At the same time, the project will apply the Multi-Objective Genetic Algorithms (MOGA) in the SOLEIL storage ring with other analysis techniques such as driving term analysis and frequency map analysis using information collected on turn-by-turn position monitors. The initial point is to identify the variables, the figure of merit and the constraints that characterise the SOLEIL machine. The first results of this optimization will be demonstrated with a serial of beam-based experiments in the SOLEIL storage ring.

Optical functions SOLEIL

‌The project will then explore new challenging optics for reducing the effective horizontal emittance of SOLEIL while keeping a large enough lifetime and injection efficiency. The reduction of the effective horizontal emittance also improves one of the most important figures of merit that characterises the synchrotron light sources: the brightness. Using the MOGA results, lists of possible upgrades for the medium term improvement plan of the facility will be obtained. The objective is to reach a horizontal emittance close to 1nm.rad.

These new findings will be applied experimentally. The aim will be to propose a set of experiments in order to check the benefits of lower horizontal emittance lattices based on photon flux, brightness, and spectral property measurement.

Finally, while keeping constant the ring circumference and the number of beamlines, a prospective work will be undertaken to evaluate exotic optics to reach sub nanometric horizontal effective emittance. The output of this work will propose directions for large modifications to the design of the storage ring lattice.

This project is the object of a PhD thesis in Paris-Sud University, France.

Images courtesy of SOLEIL

Video:

Scientist in charge:

Laurent Nadolski