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Latent diffusion can map beam loss to two-dimensional phase-space projections

Alexander Scheinker* and Alan Williams

  • *Contact author: ascheink@lanl.gov
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Phys. Rev. Accel. Beams 28, 094602 – Published 22 September, 2025

DOI: https://doi.org/10.1103/rqg9-g3dp

Abstract

Beam loss monitors (BLMs) and beam current monitors (BCMs) are ubiquitous at particle accelerators around the world. These simple devices provide noninvasive high-level beam measurements but give no insight into the detailed 6D (x,y,z,px,py,pz) beam phase-space distributions or dynamics. We show that generative conditional latent diffusion models can learn intricate patterns to solve the extreme inverse problem of mapping waveforms of tens of BLMs or BCMs along an accelerator to detailed 2D projections of a charged particle beam’s 6D phase-space density. This transformational method can be used at any particle accelerator to transform simple noninvasive devices into detailed beam phase-space diagnostics. We demonstrate this concept via multiparticle simulations of the high-intensity beam in the kilometer-long Los Alamos Neutron Science Center linear proton accelerator.

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Phys. Rev. Accel. Beams 28, 094602– Published 22 September, 2025
  • Received 1 March 2025
  • Accepted 29 August 2025
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