Conductivity induced by high LET particles

Radioactive a-sources are usually deposited on one electrode. Due to their high LET values, the range of a-particles in organic liquids is small. Range data which have been verified experimentally are compiled in Table 2. 

Since all of the energy of an a-particle is spent within the liquid, the value can be calculated just as in the case of the low LET radiation (see Equation 21). Values are compiled in Table 3. 

The Gfi(E = 0) values are much smaller than those for low LET radiation. From theoretical considerations it follows that the probability of escape of electrons from a track in the absence of an applied electric field is zero. The low yield observed is attributed to charge separation induced by 8-rays. Electrons with keV energy will become thermalized far away from their parent positive ions. The variation with 

Data from Ramy, J.P., Mesure de I energic moyenne necessaire pour crier une paire d ions dans les liquides dielectriques sous irradiation alpha, PhD Thesis, Uni-versite Paul Sabatier de Toulouse, 1971. 

Fission fragments produce dense ionization tracks from which electron escape is very low. Even at a field strength of 38 kV/cm, only 3% of the initial ionization is collected in liquid argon (Hitachi et al., 1987). 

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