Qograted in an Ud mode, the problem must be approached trom the Ph, This ecidemiological and accident statistics standpoints. because any transter of radiation energy to the i.e., is, of course, individual cells takes nlace only as a cesult of stochastic (1.e., due to random processes) between a charged particle and a target-cuntaining Thus we first need, with LLE, che (fractional) number of cells hit. Also, because energy is deposited in the TCV in separate, discrete amounts, we need also the amount of eneray deposited, 1.e., the "hit size” or "cell dose". dose varies greatly from cell The magnitude of the cell to cell, and ranges amount of kinetic energy carried by the particle. dose, to be relevant, must be registered from zero to In other words, initiation of occurs, that, while with HLE only whysical quantity organ dose is required the in individuals at the level of biological organization at which the The important conclusion is the maxinun the response of interest ., cues volume (TCV) within the cell. reesre a. encounters uc collisions the one for risk evaluation, witn LLE at phantom response Eye number of cells can be accomplished is determined electronically. This provides if hit the tor the short recovery time needed in order that many hits per cell can be recorded (i.e., if an array of phantom cells registers a total of x hits during an exposure time t, then a single “rapidly recovering” phantom cell will also register x hits during a time xt). use of the phantom will, with the appropriate scaling factor, provide us with the least two probabilities needed namely, Next, to the probability and injured. the phantom must record separately every discrete hit on the phantom cell, as well as it must provide deposits first of at in principle for epidemiological evaluation, the number of nits per cell, equal numerically that a cell will be hit, dosed, say, This property of in the amount of the energy deposited. the distribution of the magnitudes of the cell TCV's, or tie cell doses. That is This distribution of cell radiation, or any mixture. doses neatly in order of the stochastically delivered cell increasing magnitude. Thus we have the exact analogue of what is commonly used in pharmacology and toxicology -208- 9812910 to the energy doses must be obtainable for any given exposure to a single type of The electronic phantom arranges ilkacre ee and dosed during any given exposure period, the i Tee to register to he SEfeate te to be able ; ina, wives, The first requirement, te least two separate quantities are needed.