Abstract
The range of ionization chamber size to which theoretical treatments can be usefully applied is considered. The smallest size of chamber for which the Spencer-Attix theory is valid is determined by the slow electron transfer phenomenon and can be expressed mathematically. This, however, is not possible with the largest size of chamber for which theory is valid. Since the Bragg-Gray theory is based on a more approximate model than the Spencer-Attix theory and deviates more from experiment than the Spencer-Attix theory, it is convenient to express its limitations by comparison with the Spencer-Attix theory.
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