A Timepix detector covered with polyethylene convertors of different thicknesses is presented as a fast neutron real-time dosemeter. The application of different weighting factors in connection with the position of a signal in a Timepix detector enables one to obtain an energy-dependent signal equal to neutron dose equivalents. A simulation of a Timepix detector covered with polyethylene convertors using monoenergetic neutrons is presented.
View Article and Find Full Text PDFAfter an explosion of a radiological dispersal device, decision-makers need to implement countermeasures as soon as possible to minimise the radiation-induced risks to the population. In this work, the authors present a tool, which can help providing information about the approximate size of source term and radioactive contamination based on a Gaussian Plume model with the use of available measurements for liquid or aerosolised radioactivity. For two-field tests, the source term and spatial distribution of deposited radioactivity are estimated.
View Article and Find Full Text PDFResults of field tests with explosive dispersal of a radioactive substance (RaS) are presented. The paper deals with tests exploiting artificial obstacles as a continuation and expansion of the tests used in this study performed in free area described previously. The essential goal of the tests was to estimate the distribution of the released RaS in the case of intentional abuse of radioactive sources and to get a set of data applicable to testing physical or mathematical models of propagation.
View Article and Find Full Text PDFDuring recent years, the assessment of possible radiological consequences of a terrorist attack associated with a release of radioactive substances (RaS) has been in the focus of interest of emergency preparedness and radiation protection specialists, as well as experts dealing with the dispersion of harmful substances in the atmosphere. Suitable tools for these analyses are applications of mathematical and physical models and simulation of this attack under 'realistic' conditions. The work presented here summarises the results of four tests, in which a RaS (a Tc-99 m solution) was dispersed over a free area with the use of an industrial explosive.
View Article and Find Full Text PDFThe National Radiation Protection Institute in Prague is about to use a commercially available multi-element whole-body thermoluminescence dosimeter for its radiation personnel. During the phase of practical verification of the method, the dosimeter was tested, among others, in mixed neutron-photon fields in the area of interim storages for spent nuclear fuel of the Czech nuclear power plant Dukovany. The testing was made with the intention to get information about accuracy of H(p)(10) determination for cases when no site-specific calibration is available or neutron spectra are not known.
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