Evaluation of Additional Track Parameters from Fluorescent Nuclear Track Detectors to Determine the LET of Individual Ions.

The measurement of single-track intensity in fluorescence nuclear track detectors can yield relative linear energy transfer (LET)-spectra with small line-width. The absolute determination of LET is, however, currently hampered by the interdetector variability of crystal coloration and hence detector sensitivity. We therefore investigated the LET response of three additional quantities (average width and the variation of intensity and width along single tracks) using detectors irradiated with mono-energetic ion beams with LETs from 1.5 to 150 keV/mu m in alumina. All quantities showed in fact smaller interdetector variability, but at the same time larger line-width and limited dynamic range as the average intensity along a track. The additional quantities might therefore serve as a helpful complement, but not as a replacement for the current approach.