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.
@article{arxiv.1909.05963,
title = {Bayesian optimization of a free-electron laser},
author = {Joseph Duris and Dylan Kennedy and Adi Hanuka and Jane Shtalenkova and Auralee Edelen and Adam Egger and Tyler Cope and Daniel Ratner},
journal= {arXiv preprint arXiv:1909.05963},
year = {2020}
}