A Method for Measuring Half-Lives

Circular of the Bureau of Standards no. 476:

“…Kurie, Richardson, and Paxton [56] have suggested that by dividing the expression for P{r))drj by the corresponding one for the halflift!, as given by Fermi, we obtain for the number of particles N between mc-q and me (rj-t At?) NAv=Kf (Z, r,) [C-(1+T?^)V^]^{ A)v, (79) where if is a function of Z=atomic number, r=half-period, and 7?o=niomentum at the upper limit of the spectrum; and C= (1 + t?J)^''"= Eo+l, where is the energy corresponding to 7 ?o.…”

“…This usually requires that the faster rates be corrected for counting losses, a procedure that is time-consuming and difficult to do with precision. Graves and Walker [79] have suggested a method that can be used for neutron-activated isotopes, which eliminates the correction for counting losses.…”