Abstract
The formulae for the number of counts per minute of beta-rays ejected from homogeneous rocks or ores and detected by an end-window Geiger-Mueller counter at a distance more than four centimetres have been calculated with the results as follows:
T=60πpNW/C*G,
where
G=e-μ*AH/[cosδ]g,
g=(tan-1H2+x12/XH-tan-1H/X)XH/4,
or
g=(1/H2-1/H2+X12)S0H4,
and μ*A: the absorption coefficient for air regarding the number of betarays (cm-1),
[cos δ]: the mean velue of cos δ,
S0: the effective solid angle at the point in which the extension of the central line of Geiger-Mueller tube meets the surface of the object,
other notations being the same as in the previous report.
