Concepts of microdosimetry. I. Quantities.

This is the first part of an investigation of microdosimetric concepts relevant to numerical calculations. The definitions of the microdosimetric quantities are reviewed and formalized, and some additional conventions are adopted. The common interpretation of the quantities in terms of energy imparted to spherical sites is contrasted with their interpretation as the result of a diffusing process applied to the initial spatial pattern of energy transfers in the irradiated medium.