ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
Explore the many uses for nuclear science and its impact on energy, the environment, healthcare, food, and more.
Division Spotlight
Nuclear Installations Safety
Devoted specifically to the safety of nuclear installations and the health and safety of the public, this division seeks a better understanding of the role of safety in the design, construction and operation of nuclear installation facilities. The division also promotes engineering and scientific technology advancement associated with the safety of such facilities.
Meeting Spotlight
International Conference on Mathematics and Computational Methods Applied to Nuclear Science and Engineering (M&C 2025)
April 27–30, 2025
Denver, CO|The Westin Denver Downtown
Standards Program
The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
Latest Magazine Issues
Apr 2025
Jan 2025
Latest Journal Issues
Nuclear Science and Engineering
June 2025
Nuclear Technology
Fusion Science and Technology
May 2025
Latest News
Argonne’s METL gears up to test more sodium fast reactor components
Argonne National Laboratory has successfully swapped out an aging cold trap in the sodium test loop called METL (Mechanisms Engineering Test Loop), the Department of Energy announced April 23. The upgrade is the first of its kind in the United States in more than 30 years, according to the DOE, and will help test components and operations for the sodium-cooled fast reactors being developed now.
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.