Spectrometry of the LET with track etched detectors—correlation with proportional counter measured spectra

Abstract

A spectrometer of the linear energy transfer (LET) based on the chemically etched polyallyldiglycolcarbonate (PADC) track etched detector was developed. The LET spectra are determined through the measurements of track parameters, it covers LET range between 10 and 700 keV/ μm in tissue. A combined experimental and theoretical approach allowed the estimation of the critical dimensions of the sensitive volume necessary for developing a track to several nm. It seemed interesting to us to compare the LET spectra obtained by this method with the microdosimetric spectra available on the basis of a classical experimental microdosimetry method, a tissue equivalent proportional counter, for which the critical dimensions simulated are of the order of a few μm. Both methods of experimental microdosimetry were compared in the high energy radiation reference fields and on the subsonic aircraft board. It was found out that the microdosimetric distributions are similar; some differences are, nevertheless, observed. Further studies with the goal to explain them are outlined.