Nuclear weapons test, characterization

Cooper MB, Bums PA, Tracy BL, et al. 1994. Characterization of plutonium contamination at the former nuclear weapons testing range at Maralinga in South Australia. J Radioanal Nucl Chem 177(1) 161-184. 

The Characterization of Radioactive Particles from Nuclear Weapons Tests... 

Storm of Jan. 20-23, 1967. This storm was characterized by the large (<— 200 kilotons) atmospheric nuclear weapon test of the Chinese (China-5) on Dec. 28, 1966. The pertinent ratio data are given in Table X. The first California storm occurred 25.6 days later. Another possible source of fresh fission products was the reported venting of a U.S.S.R. underground nuclear detonation on Dec. 18, 1966 (17). The prior Chinese and French atmosphere tests occurred 85 to 109 days before the storm date less than 1% of the 140Ba could have come from China-4 and less than 7% from the French tests. 89Sr was still present from the prior tests only 3% was left from the China-3 test of May 9, but the activity levels would still be measurable. 

Nuclear weapons testing fallout, which is characterized by a pulse-like injection into the atmosphere predominantly in the 1950s and 1960s, and includes the radioisotopes... 

Figure 6 is a schematic of the time history of representative tracers characterized by the first two types of release styles for the northern hemisphere. Three of the tracers (radiocarbon and the CFCs) are gaseous phase tracers, and are consequently relatively homogeneously distributed between the hemispheres, with the northern hemisphere leading the southern hemisphere by l-2yr both CFCs and radiocarbon were released preferentially in the northern hemisphere. Radiocarbon was released from atmospheric nuclear weapons tests that were almost solely in the northern hemisphere, and CFC releases were dominated by North American, European, and Soviet production. The time lag... 

Although the transient test was orders of magnitude below a nuclear weapon in regard to energy release and temperature achieved, the debris showed many similarities to fallout. These included not only the size and appearance of the particles but also the correlation properties of various radionuclides. Dissimilarities in the correlations and the variation of specific activity with particle type confirm expectations of the importance of escape processes to the formation mechanisms for this type of debris. This study shows that data-correlation techniques developed for fallout characterization are also useful in studying reactor debris. 

Six plutonium containing particles stemming from soil (Marshall Island) were characterized by SIMS, SEM-EDX-WDX and sychrotron radiation by Jernstrom et al. AU the particles were identified as nuclear fuel fragments of exploded weapons components. Since they contained plutonium with a low °Pu/ Pu atomic ratio (less than 0.065), which corresponds to weapons grade plutonium or a detonation with low fission yield, the particles were identified as originating from the safety test and low yield tests conducted on Runit Island. ... 

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