Experimental approach to chernobyl hot particles

Radioactive Particles in the Environment

“…Two particles (denoted as 1542 and 1543) were found in the soil layer at 20-25 cm below the soil surface and the particle denoted as HOT PARTICLES IN THE FLOODPLAIN OF THE YENISEI RIVER 113 1544 was found at a depth of 5-10 cm. The hot particles were cleaned in isopropanol to remove soil adhering to them (Tcherkezian et al, 1994). Some of the particles were found in the top soil layer, the others -in the 10-15 cm layer (Tables 1 and 2).…”

“…The radiochemical methods for concentration and refinement of the elements are described in detail elsewhere (Tcherkezian et al, 1994;Bolsunovsky, Tcherkezian, 2001). Spectra were analyzed using GENIE PC software ("Canberra").…”

Monte Carlo Simulation Study of Hot-Particle Detection in Voluminous Samples by Gamma Spectrometry

“…The n-particle model assumes that all particles have the same activities. It was observed that hot particles from nuclear accidents exhibit distribution of sizes [14], often assumed lognormal [15]. Then, constant specific activity implies lognormal distribution of activities as well.…”

“…The Chernobyl particles can be mono-elemental, bi-elemental, or fuel fragments [13], whereas Fukushima particles contain predominately 137 Cs, referred to as Cs microparticles [12]. Hot particles can have diameters from a fraction of a micrometer to over 100 μm [14] and their size distribution is often assumed as lognormal [15] or arbitrary [16].…”

“…A voluminous sample can contain both uniformly distributed radioactivity as well as inhomogeneous hot particles. It was estimated that at least 65% of total activity in the 30-km zone around Chernobyl was due to hot particles [14]. Statistical modeling methods have been developed based on either splitting of a large sample and measurement of several sub-samples on a gamma spectrometer [15] [35], or repetitive mixing and measuring of the same sample [36] [37] [38].…”