Parity violation in hydrogen and longitudinal atomic beam spin echo I T. Bergmann, M. DeKieviet, T. Gasenzer, O. Nachtmann and M.-I. Trappe Eur. Phys. J. D, 54 3 (2009) 551-574 Published online: 23 June 2009 DOI: 10.1140/epjd/e2009-00179-4