We tabulate the beta-decay half-lives
respect to Gamow-Teller transitions.
The β+ number is the
half-life with respect to both beta-plus and electron-capture decay.
We also tabulate the probabilites
PA-k for producing a final nucleus
with mass number A-k following beta decay and
delayed emission of k neutrons. These probabilities
are closely related to beta-delayed neutron-emission probabilities.
The beta-decay Q values and neutron separation energies
used in these calculations were obtained from
experimental mass differences when such masses
were available, otherwise from calculated masses.
The beta-delayed occupation probabilities are only calculated
inside the calculated neutron drip line in the daughter of the
Please note that:
1. The half-lives are calculated with respect to Gamow-Teller transitions.
Fermi transitions and forbidden transitions are not considered.
2. The calculated half-lives close to stability are fairly uncertain because (a) we do not consider forbidden transitions and (b) close to stability small decay Q values enhance the effect of small uncertainties in the calculated position of the levels involved in the decay. An error of 500 keV in the postion of a level may change the calculated value by many orders of magnitude, or even from say a few minutes to infinity! Far from stability the same absolute error has a much lower effect on the calculated half-life, for example less than a factor of two at beta-decay Q values around 10 MeV.
Three different data files are available for downloading: