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Latest News
Framatome, KHNP to investigate producing Lu-177 in South Korea
Framatome and Korea Hydro & Nuclear Power (KHNP) announced the signing of a memorandum of understanding to explore the possibility of producing the medical isotope Lutetium-177 at KHNP’s Wolsong nuclear power plant in South Korea. The companies also will investigate the feasibility of using the plant to support Korean production of medical radioisotopes in the future.
Lénard Pál, Imre Pázsit
Nuclear Science and Engineering | Volume 184 | Number 4 | December 2016 | Pages 537-550
Technical Paper | doi.org/10.13182/NSE16-18
Articles are hosted by Taylor and Francis Online.
The Campbell theorem, relating the variance of the current of a fission chamber (a “filtered Poisson process”) to the intensity of the detection events and to the detector pulse shape, becomes invalid when the neutrons generating the fission chamber current are not independent. Recently, a formalism was developed by the present authors, by which the variance of the detector current can be calculated for detecting neutrons in a subcritical multiplying system, where the detection events are obviously not independent. In the present paper, the previous formalism, which only accounted for prompt neutrons, is generalized to account also for delayed neutrons. A rigorous probabilistic analysis of the detector current was performed by using the same simple, but realistic detector model as in the previous work. The results of the present analysis made it possible to determine the bias of the traditional Campbelling techniques both qualitatively and quantitatively. The results show that the variance still remains proportional to the detection intensity, and is thus suitable for the monitoring of the mean flux, but the calibration factor between the variance and the detection intensity is an involved function of the detector pulse shape and the subcritical reactivity of the system, which diverges for critical systems.