Neutron dose estimation via LET spectrum measurement using CR-39 detectors

Linear energy transfer (LET) spectrum is crucial for determining the energy deposition in microscopic level to estimate the absorbed dose (DLET) and dose equivalent (HLET) in cellular or sub cellular volumes. In this work, we report the neutron dose estimation by measuring the LET spectrum using CR-39 track detectors for two available standard neutron sources, i.e., 241Am-Be and 252Cf. The etching parameter, i.e., thickness of the removed surface after etching and the track parameters such as major and minor radii are taken into account for the measurement of the LET spectrum. The measured LET spectrum extends from 12 keV/μm to 405 keV/μm. The contribution to the higher LET portion of the spectrum can be attributed to neutron-induced carbon and oxygen recoils in the detectors which are found more to be more in case of 241Am-Be than 252Cf. The microdosimetric distributions of DLET and HLET obtained using the Q-L relationship given by ICRP 60. The dose equivalent values (HLET) per unit fluence are found to be about 65 and 70 pSv.cm2 for 241Am-Be and 252Cf sources respectively. (author)