Advantages of solid state nuclear track detectors for the assessment of alpha emitters and fissile elements

Solid-state track detectors in radiometry, isotope analysis, and radiography

“…These measurements usually take advantage of the possibility of measuring very low α-activity levels by performing long exposures (for weeks and months). For example, at a 1-month exposure, it is possible to determine the α-particle flux density of 10 -4 Bq cm -2 [9].…”

“…In this case, it is necessary to chemically purify the sample to remove Pu and/or to determine the Pu impurity by radiometric (spectrometric) or other methods. Similarly, the most widely used methods for determining Pu in a mixture with U are chemical recovery of Pu with its purification [5,40] and a combination of measuring the number of fission events and the α-activity [9].…”

“…The following properties of SSTDs are favorable for this purpose: (1) threshold sensitivity of SSTDs to charged particles, which allowed recording of α-particles and fission products against high β,γ-radiation background typical of accidental contaminations; (2) high sensitivity of the methods, allowing monitoring of the migration pathways of α-emitters in soil, water, and biological objects and evaluation of the decontamination efficiency; and (3) possibility of gaining radiographic information on contaminated objects, which is very important taking into account the spatial nonuniformity of contaminations, usually strongly pronounced, and the presence of "hot particles." SSTDs were used for determining the size of plutonium particles in soils on sites of previous tests of British nuclear weapons (Maralinga, South Australia) [9,101]. Both the α-ray method with CR39 and the neutron irradiation with mica were used.…”

“…The sample pretreatment was necessary because the contamination was highly nonuniform [63,64]. Very important problems of sample homogenization were considered in [9,15,[65][66][67]. The pretreated samples, as a rule, were pressed to obtain standard pellets onto which CN or CR-39 detectors were applied.…”

“…In this review I mainly consider the general characteristics of radiometry, isotope analysis, and autoradiography using SSTDs, and also some results of applying the method to physical, chemical, and technological studies. The results of using the method in geology, biology, medicine, ecology, materials science, and radiobiological and nuclear-physical experiments (including synthesis of superheavy elements) are considered in monographs [1,6,7] and in specialized reviews, e.g., in [8][9][10][11][12][13]. The results of autoradiographic studies in various branches of science and engineering have been reported at 16 international symposia on autoradiography, which were regularly held up to 1988.…”