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Determine whether diffusion driven by transverse-feedback and external noise, which flattens the tails of the particle distribution and shrinks the stability diagram, accounts quantitatively for measured latencies and octupole thresholds.","problem_ref":null,"references":"","settled_by":"Controlled noise-injection experiments in which measured latency versus noise level matches a diffusion model with no fitted parameters.","status_note":"Noise-driven erosion of Landau damping was proposed and supported by simulations and dedicated LHC experiments around 2019-2021; predictive accuracy for operation is limited.","title":"Instabilities that appear minutes after a beam is predicted 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