Testing CP Violation in the Higgs Sector at Muon Colliders
  We study the possibility of measuring the muon Yukawa couplings in s-channel Higgs boson production at a muon collider with transversely polarized beams. We investigate sensitivity to the relative size of the CP-odd and CP-even muon Yukawa couplings. Provided the event rate observed justifies the operation of the mu+mu- Higgs boson factory, we find that 40% polarization for both beams is sufficient to resolve the CP nature of a single resonance as well as disentangle it from two overlapping CP conserving resonances. 
Bohdan Grzadkowski (Warsaw U.), John F. Gunion (UC, Davis) and Jacek   Pliszka(Warsaw U.)