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Determine whether a realistic 6D cooling channel plus final cooling stage can reach normalized transverse emittance of approximately $2.5 \\times 10^{-3}$ cm and longitudinal emittance of approximately $7\\,\\mathrm{cm}$ with overall muon transmission above $\\sim 10$ percent, including RF limits in solenoid fields, absorber heating, space charge and muon decay.","problem_ref":"dea5b75dcdbb182ed7a0e7fd916ec327dd01d61c06f3a389f15cf952a3454e20","references":"","settled_by":"An end-to-end simulation with engineering-feasible fields and gradients reaching both emittances, confirmed by a 6D cooling demonstrator for the first stages.","status_note":"","title":"Reaching muon collider target emittances by ionization 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