New determination of true net count-rates with 'proportional' sources of a radioisotope

Over the entire range of the observed net rate Rsub(j), the values of the experimental observed-to-true net count-rate ratio, Rsub(j)/R0sub(j) < 1, of any source Ssub(j) may be evaluated by a series of sources S1,...,Ssub(n), Ssub(n+1)..., which are identical except for their widely differing true net rates R10 < R20 <,.... The experimental values of R0sub(j)/R0sub(p) for sources Ssub(j) and Ssub(p) can be accurately determined, e.g. by weighing the masses, m1 < m2 <,..., of portions of a radioisotope solution. In this case R0sub(j)/R0sub(p) msub(j)/msub(p), where R0sub(p) and msub(p) are constants and j = p + 2,..., at p = 1 to n - 2. (e.g. R20/R10 = 5-10, R30/R10 10-20,..., at p = 1.) The observed total rates with a constant background rate Rsub(b), R1 + Rsub(b) < R2 + Rsub(b) <,..., of the sources should be measured under identical measurement conditions. From the experimental ratios Rsub(j)/Rsub(p) and R0sub(j)/R0sub(p) (j = p + 1, p + 2,..., at p = 1 to n-2) the values of Qsub(p)sup(j) Rsub(j)/Rsub(p)/(R0sub(j)/R0sub(p)), < 1 can be determined experimentally over the whole range of the observed net rate Rsub(j). For evaluating Rsub(j)/R0sub(j) vs Rsub(j) the linear portion of Qsub(p)sup(j) vs Rsub(j) can be determined with sources S1 to Ssub(n), and the nonlinear portion with the sources Ssub(n + 1), Ssub(n + 2), etc. The use of the procedure for determining the linear and nonlinear portions of Rsub(j)/R0sub(j) vs Rsub(j) was proved by experimental data. (author)