Time asymmetric quantum theory and the ambiguity of the Z-boson mass and width A. Bohm, N.L. Harshman, H. Kaldass and S. Wickramasekara Eur. Phys. J. C, 18 2 (2000) 333-342 Published online: 27 November 2000 DOI: 10.1007/s100520000411