CP violation in heavy neutrino mediated e−e− → W−W−

We consider the reaction e−e− → W−W− mediated by possible heavy neutrino exchange at future LINAC energies of s ⪢ 2mw. This reaction is sensitive to CP phases of the neutrino mixing matrices, even at the level of Born amplitudes. Certain integrated cross-sections are shown to have the power to resolve the CP phases when the experimental configurations are varied. Asymmetries sensitive to CP violation (involving initial QED phases) for e−e− and e+e+ reactions are constructed and their consequences considered.