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Determine whether conductor layout (striated tapes, round twisted-tape cables) and ramp protocols can reduce screening-current field errors below $1e-4$ at fields $1e5\\ \\text{to}\\ 2e5\\,\\mathrm{G}$, and predict their decay in time from flux-creep parameters of the tape.","problem_ref":null,"references":"","settled_by":"Magnetic measurements of field harmonics and their time decay in a REBCO dipole insert, matched by a model using independently measured tape properties.","status_note":"","title":"Field errors from screening currents in REBCO accelerator 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