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arXiv · 1909.05963

Bayesian optimization of a free-electron laser

Joseph Duris·Dylan Kennedy·Adi Hanuka·Jane Shtalenkova·Auralee Edelen·Adam Egger·Tyler Cope·Daniel Ratner
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Abstract

The Linac Coherent Light Source changes configurations multiple times per day, necessitating fast tuning strategies to reduce setup time for successive experiments. To this end, we employ a Bayesian approach to transport optics tuning to optimize groups of quadrupole magnets. We use a Gaussian process to provide a probabilistic model of the machine response with respect to control parameters from a modest number of samples. Subsequent samples are selected during optimization using a statistical test combining the model prediction and uncertainty. The model parameters are fit from archived scans, and correlations between devices are added from a simple beam transport model. The result is a sample-efficient optimization routine, which we show significantly outperforms existing optimizers.

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Joseph Duris, Dylan Kennedy, Adi Hanuka, Jane Shtalenkova, Auralee Edelen, Adam Egger, Tyler Cope, Daniel Ratner. 2019-09-12. Bayesian optimization of a free-electron laser. https://doi.org/10.1103/physrevlett.124.124801

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