Use of defined solid angle absolute β counting for environmental radioanalytical purposes. Part 1. Methods

Defined solid angle absolute β counting of thick samples using end-window Geiger-Muller counter is shown to be a useful method in the field of environmental radio analysis. Some new proposals in connection with the possibility of the reduction and evaluation of the correction factors for the numerous effects responsible for losses and gains in the β counting rate are made on the basis of a comprehensive review of the literature on this topic. A new formula is proposed in order to evaluate correction factors for internal back scattering within thick samples. The case of the exponential decrease of activity as function of the thickness in filter-type samples is treated. 1 fig., 48 refs