Study of materials for mixed field dosimetry by EPR spectroscopy.

EPR dose reconstruction after accidental photon exposure based on materials irradiated in the vicinity of the victim (sucrose, medicine tablets, etc.) was used successfully in several cases referenced in the literature. However, accidental exposure may also occur with a neutron component such as in the Tokai-Mura criticality accident. The aim of this work is to investigate the potentiality of EPR dosimetry for mixed photon and neutron field exposure with different organic materials already used for photon exposure (sucrose) or with potential dosimetric properties (ascorbic acid, sorbitol, glucose, galactose, fructose, lactose and mannose). To assess the neutron sensitivity, the materials were exposed to a mixed radiation field of an experimental reactor with different neutron to photon ratios. The relative neutron sensitivity was found to range from 12 to 43% according to the materials. The potentiality of these materials for mixed field EPR dosimetry is discussed.