CP violation at a linear collider with transverse polarization

Transverse polarization (TP) enables novel CP violation search in the inclusive process e+e- -> A+X. When the A spin is unobserved and m_e neglected, only (pseudo-)scalar or tensor currents associated with a new-physics scale Lambda can lead to CP-odd observables at leading order in the couplings from interference with gamma and Z in the presence of TP. Without TP, these couplings can be probed only at higher order, and with loss of statistics entailed by the measurement of A polarization. For e+e- -> t tbar, an azimuthal CP asymmetry can yield at 90% C.L. a bound on Lambda of approximately 10 TeV for sqrt{s}=500 GeV and L=500 fb^-1 with perfect TP