Fig. (22) Sensitivity to the neutrino mass at the 90% CL predicted for the measurement of radioactive ions in a storage ring [166]. in the figure is identical with mvedefined in Eq. (5) of this work.) Two β-emitters with energies Q = 5 and 3 keV, and total amount of 1018 and 1019 recorded decay events, respectively, are considered. Three effects influencing were examined: a normalization uncertainty σnorm on the beam flux (left panel), background Nbackground in the backward detector (middle panel) and a momentum spread δpI/pI of the initial ion (right panel).