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Division Spotlight
Accelerator Applications
The division was organized to promote the advancement of knowledge of the use of particle accelerator technologies for nuclear and other applications. It focuses on production of neutrons and other particles, utilization of these particles for scientific or industrial purposes, such as the production or destruction of radionuclides significant to energy, medicine, defense or other endeavors, as well as imaging and diagnostics.
Meeting Spotlight
2023 ANS Winter Conference and Expo
November 12–15, 2023
Washington, D.C.|Washington Hilton
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!
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Nuclear Science and Engineering
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Latest News
Standard on fixed neutron absorbers in nuclear facilities outside reactors just issued (ANS-8.21)
ANSI/ANS-8.21-2023, Use of Fixed Neutron Absorbers in Nuclear Facilities Outside Reactors, has just been issued by the American Nuclear Society Standards Committee. The standard was approved by the American National Standards Institute (ANSI) on June 20, 2023, as a revision and consolidation of ANS-8.21-1995 (R2019) (withdrawn) (same title) and ANS-8.5-1996 (R2022) (withdrawn), Use of Borosilicate-Glass Raschig Rings as a Neutron Absorber in Solutions of Fissile Material. ANSI/ANS-8.21-2023 provides guidance for the use of neutron absorbers, including Raschig rings, as an integral part of nuclear facilities equipment, fissile material, or fuel components outside reactors, where such absorbers are credited to provide criticality safety control.
R. D. M. Garcia, C. E. Siewert, J. R. Thomas Jr.
Nuclear Science and Engineering | Volume 186 | Number 2 | May 2017 | Pages 103-119
Technical Paper | doi.org/10.1080/00295639.2016.1273627
Articles are hosted by Taylor and Francis Online.
The long-standing problem of implementing the PN method effectively for spherical geometry is revisited in this work. It is shown that a least-squares approach to the method resolves to a great extent the numerical instability reported for the first time by Aronson in 1984. In the proposed version of the method, a small loss of accuracy is still observed for intermediate orders of the approximation, but in high order (typically N ≥ 199), full accuracy is recovered, and the method can be used with confidence even for extremely high orders of the approximation. Numerical results of benchmark quality are tabulated for the quantities of interest for two basic transport problems in spherical geometry: the albedo problem for a sphere and the critical-sphere problem, both including cases that show the effects of scattering anisotropy described by the binomial law.