21Na and 29P Q-value measurements

Published: October 2015 Brodeur

Lead Author(s): M. Eibach

The Q-value of the 21Na and 29P superallowed decays were measured with the LEBIT Penning trap at the NSCL. This new 21Na Q-value is 3 times more precise than the literature, while 29P mass was measured directly for the first time. The uncertainty level of the Q-values are now at the same level as the theoretical corrections used to determine the ft-value. The Vud matrix element obtained from mirror transitions is now 1.3s lower than the value obtained from pure Fermi transition. More precise determinations of the Fermi-to-Gamow Teller mixing ratios will be needed to clarify the situation. Learn more

Determination of the QEC values of the T=1/2 mirror nuclei 21Na and 29P at LEBIT