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IAEA report confirms safety of discharged Fukushima water
An International Atomic Energy Agency task force has confirmed that the discharge of treated water from Japan’s Fukushima Daiichi nuclear power plant is proceeding in line with international safety standards. The task force’s findings were published in the agency’s fourth report since Tokyo Electric Power Company (TEPCO) began discharging Fukushima’s treated and diluted water in August 2023.
More information can be found on the IAEA’s Fukushima Daiichi ALPS Treated Water Discharge web page.
E. Rich, Gilles Noguere, C. De Saint Jean, A. Tudora
Nuclear Science and Engineering | Volume 162 | Number 1 | May 2009 | Pages 76-86
Technical Paper | doi.org/10.13182/NSE162-76
Articles are hosted by Taylor and Francis Online.
For the modeling of the neutron cross sections, three energy ranges can be distinguished. The resolved resonance range can be interpreted in terms of single-level, multilevel, Reich-Moore, or R-matrix parameters. The unresolved resonance range (URR) is described with the average R-matrix and Hauser-Feshbach formalisms. For the high energies ("continuum"), optical model parameters are used in association with statistical and preequilibrium models. One of the main challenges of such a work is to study the consistency of the average parameters obtained by these different calculations. With the ESTIMA and SPRT methods, we provide a set of parameters for partial s-waves and p-waves (strength functions Sl and effective potential scattering radius R'). However, accurate analysis of the URR domain needs more information than parameters R' and Sl associated with orbital moments l = 0 and l = 1. Using links between the average R-matrix formalism and the optical model calculations, we propose a generalization of the SPRT method for l > 1 and a new description of the URR domain in terms of Sl and RlJ.
