Mass (The Ame2012 atomic mass evaluation (II) by M.Wang, G.Audi, A.H.Wapstra, F.G.Kondev, M.MacCormick, X.Xu, and B.Pfeiffer
Chinese Physics C36 p. 1603-2014, December 2012)
221.021228000 ± 0.000021000 (amu) [mass excess = 19773.755 ± 19.561 (keV) ]
Beta-decay energy (calculated as M(A,Z)-M(A,Z+1), taken from Ame2012)
2991.027 ± 24.039 (keV)
Evaluated Data Libraries
Links to the libraries.
Parent Nuclides by Reactions in JENDL-4.0