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Reconcile with CERN SPS measurements in which TMCI is suppressed but other instabilities appear at high space charge.","problem_ref":null,"references":"","settled_by":"A self-consistent theory or converged simulation that reproduces the measured SPS thresholds versus space-charge strength without free parameters.","status_note":"Models published 2016-2018 give thresholds rising or falling with space charge depending on wake sign and phase advance; SPS experiments reported in 2022 saw TMCI replaced by other instabilities at high space charge.","title":"Effect of space charge on the transverse mode-coupling instability 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