To the spectrometry of linear energy transfer in charged particle beams by means of track-etch detectors

Abstract

The contribution describes the methodology of linear energy transfer (LET) spectrometry based on the chemically etched track detectors and results of some experimental studies. Three types of polyallyldiglycolcarbonate (PADC) material have been used in our laboratory: Page—with a thickness of 0.5 mm and Tastrak with thicknesses of 0.5 and 1 mm. This LET spectrometer is able to detect charged particles with LET above the registration threshold (around 10 keV / μ m , depending on the used material), both primary and secondary, created through nuclear interactions in the detector itself or in the surroundings. During several years the detectors were irradiated by various particles with LET in water up to about 600 keV / μ m . In these studies, primary heavy ions had LET above the registration threshold and so they can be directly detected. However, also some fragments and products of nuclear reactions of the primary particles are registered in the detector, especially behind various absorbers. LET spectrometer calibration curves and also the importance of secondary particles in heavy ion beams and their contribution to the absorbed dose are presented and discussed.