The radiochromic dye film dose meter as a possible test of particle track theory

The response characteristic of the thin-film radlochromlc dye cyanide plastic dose meter to Ionizing radiation of electrons and heavy charged particles Is Investigated as a possible test of the particle track theory worked out by Robert Katz and coworkers.

Dose response curves for low-LET radiation have been Investigated and are used for a qualitative estimation of the response for protons and oxygen Ions at 16 and 4 MeV/amu, respectively. A bleaching effect on the colouration at high doses Intimates that the target cannot be Interpreted literally, but it might still be possible to transfer the function of the macroscopic dose response to a theoretical dose response curve In a microscopic scale for a single Ion. From this relation the macroscopic dose response curve can be determined when the film is irradiated with heavy ions.

It will be shown theoretically that for protons there is no saturation in the track core, whereas calculations for oxygen ions show a heavy saturation in the track core, which means that a part of the ions loose their energy ineffectively. We can conclude that it is possible qualitatively to predict the dose response curve for high-LET particles by means of the dose response curve for low-LET radiation.