Simulation Only

D. Meier1, L. V. Ramirez1, J. Völker1, J. Viefhaus1, B. Sick2, G. Hartmann1 1Helmholtz-Zentrum Berlin, 2University of Kassel Physical Review Accelerators and Beams Abstract Superconducting photoelectron injectors are promising for generating highly brilliant pulsed electron beams with high repetition rates and low emittances. Experiments such as ultrafast electron diffraction, experiments at the Terahertz scale, and energy recovery linac applications require such properties. However, optimizing the beam properties is challenging due to the high number of possible machine parameter combinations. This article shows the successful automated optimization of beam properties utilizing an already existing simulation model. To reduce the required computation time, we replace the costly simulation with a faster approximation with a neural network. For optimization, we propose a reinforcement learning approach leveraging the simple computation of the derivative of the approximation. We prove that our approach outperforms standard optimization methods for the required function evaluations given a defined minimum accuracy. ...

E. Meier, Y.-R. E. Tan, G. S. LeBlanc Australian Synchrotron 3rd International Particle Accelerator Conference Abstract This paper reports the use of neural networks for orbitcorrection at the Australian Synchrotron Storage Ring. Theproposed system uses two neural networks in an actor-criticscheme to model a long term cost function and computeappropriate corrections. The system is entirely based onthe history of the beam position and the actuators, i.e. thecorrector magnets, in the storage ring. This makes the sys-tem auto-tuneable, which has the advantage of avoiding themeasure of a response matrix. The controller will automat-ically maintain an updated BPM corrector response matrix.In future if coupled with some form of orbit response anal-ysis, the system will have the potential to track drifts orchanges to the lattice functions in ”real time”. As a genericand robust orbit correction program it can be used duringcommissioning and in slow orbit feedback. In this study,we present positive initial results of the simulations of thestorage ring in Matlab. ...