State of the Art in Electronic Dosemeters for Neutrons

Abstract

Articles you may be interested in 3D printer generated thorax phantom with mobile tumor for radiation dosimetry Rev. Sci. Instrum. 86, 074301 (2015); Abstract. The paper presents an overview of electronic personal dosemeters for neutrons in mixed neutron/photon fields. The energy response of commercially available electronic dosemeters in quasi-monoenergetic neutron fields and their performance in working places is discussed. The response curves are extended to high-energy neutrons up to 100 MeV, new prototype dosemeters are described and discussed especially for use at high-energy accelerators and in space.Electronic personal dosemeters for neutrons are much less developed than those for photon and beta radiation fields. After an introduction on quantities measured in personal dosimetry, a short overview of the performance of electronic dosemeters for photons and electrons is given. This is followed by a description of the general problems for the development of neutron dosemeters, i.e. the huge range of neutron energies encountered in workplace fields, the limited number of nuclear reactions available for detecting these neutrons and the problems involved in the discrimination of photon-induced signals in mixed neutron-photon radiation fields.First, the performance of passive personal neutron dosemeters is described for the two main detection methods in routine use, i.e. that of TLD-Albedo dosemeters and nuclear track dosemeters. This is followed by the description of the performance of commercially available electronic neutron dosemeters, most of them based on silicon detectors, and some prototype dosemeters, based on special silicon detectors, bubble detectors, direct ion storage (DIS) detectors and tissue equivalent counters (TEPCs). The results of measurements in calibration fields and in workplace fields of the nuclear industry are presented. In addition, the existing neutron energy responses of dosemeters are updated to higher energies, up to about 100 MeV, in order to estimate the readings of these dosemeters behind the heavy shielding of high-energy accelerators, i.e. for use in ion therapy.At the end, a short outlook is given of the development of electronic personal dosemeters for astronauts. The radiation field in space is even much more complex since it includes not only neutrons and photons, but also ions and electrons and dose equivalent spectra extend to even higher energies.

Characterization of silicon carbide and diamond detectors for neutron applications

“…However, the SiC detectors did demonstrate the lowest neutron-gamma crosssensitivity ratio relative to Co-60 photons (E max [AmBe] / E max [Co-60]≈6.5), with D-PC providing the best ratio (16). This suggests that there could be more difficulty in discriminating gamma-ray interference from direct neutron detection in the SiC relative to the other detectors.…”

“…For most devices, neutron detection in electronic dosemeters is achieved by using Si detectors with several neutron conversion layers [14,15] to give a characteristic energy response, which for the most part is similar for the majority of devices on the market [16,17]. However, maintaining a flat dose equivalent response over such a wide range of energies (0.025 eV to 15 MeV) is extremely difficult, with the neutron personal dose equivalent relative response of these devices often ranging from ≈0.1 to 15 [16].…”