The activation of these elements, homogeneously contained in a medium thicker than the path length, of slowing-down capacity
close to that of aluminium, was determined as a function of energy by irradiating standards with p, d,3He and α particles of energies between: 5 and 15 MeV for protons, 5 and 20 MeV for deuterons and3He particles, 25 and 42 MeV for α particles. The detection sensitivities intrinsically possible in these energy ranges are
deduced from the curves obtained. The results apply to all materials through a simple relationship taking into account the
path lengths. They may be used in particular to foresee the possibilities offered by activation with these charged particles,
from the viewpoint of sensitivity, when the samples to be analysed are irradiated with a beam of given intensity and energy
lying between the above limits.