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Title: High-dimensional maximum-entropy phase space tomography using normalizing flows

Journal Article · · Physical Review Research

Particle accelerators generate charged-particle beams with tailored distributions in six-dimensional position-momentum space (phase space). Knowledge of the phase space distribution enables model-based beam optimization and control. In the absence of direct measurements, the distribution must be tomographically reconstructed from its projections. In this paper, we highlight that such problems can be severely underdetermined and that entropy maximization is the most conservative solution strategy. We leverage —invertible generative models—to extend maximum-entropy tomography to six-dimensional phase space and perform numerical experiments to validate the model's performance. Our numerical experiments demonstrate consistency with exact two-dimensional maximum-entropy solutions and the ability to fit complicated six-dimensional distributions to large measurement sets in reasonable time. Published by the American Physical Society 2024

Sponsoring Organization:
USDOE
Grant/Contract Number:
AC05-00OR22725
OSTI ID:
2429131
Journal Information:
Physical Review Research, Journal Name: Physical Review Research Journal Issue: 3 Vol. 6; ISSN 2643-1564; ISSN PPRHAI
Publisher:
American Physical SocietyCopyright Statement
Country of Publication:
United States
Language:
English

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