The muon collider as a factory.

Abstract: We show that a muon collider is ideally suited for the study of heavy scalars, cousins of the Higgs boson found in two-Higgs-doublet models and required in supersymmetric models. The key aspects of are: (1) they are narrow, yet have a width-to-mass ratio far larger than the expected muon collider beam-energy resolution, and (2) the larger muon Yukawa allows efficient s-channel production. We study in detail a representative Natural Supersymmetry model which has a with . The large event rates at resonant peak allow the determination of the individual H and A resonance parameters (including CP) and the decays into electroweakinos provide a wealth of information unavailable to any other present or planned collider. [Copyright &y& Elsevier]