Can a muon collider measure W boson mass better than today?

Physicists simulated precision measurements at a proposed 10 TeV muon collider, focusing on W boson production via photon fusion and decay into quarks. The hadronic decay channel could improve on the current ~10 MeV uncertainty in W mass measurements, and more surprisingly, could determine CKM matrix elements like Vcb far better than current low-energy methods—sidestepping the murky theoretical uncertainties in those extractions. The results hinge on building detectors that measure hadronic energy with extreme fidelity.