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Fusion Science and Technology
Latest News
In transition: Commercializing fusion power
Commercial fusion power is closer than ever. There are now around 30 U.S. fusion companies, several of which claim to be on track to connect to the grid as early as the 2030s.
Tokamak and laser inertial confinement approaches benefit from decades of research at facilities such as the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory and ITER, with alternative concepts including stellarator, magnetic mirror, and Z-pinch confinement also making notable progress as private and government funding for fusion increases.
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.