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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.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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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General Kenneth Nichols and the Manhattan Project
Nichols
The Oak Ridger has published the latest in a series of articles about General Kenneth D. Nichols, the Manhattan Project, and the 1954 Atomic Energy Act. The series has been produced by Nichols’ grandniece Barbara Rogers Scollin and Oak Ridge (Tenn.) city historian David Ray Smith. Gen. Nichols (1907–2000) was the district engineer for the Manhattan Engineer District during the Manhattan Project.
As Smith and Scollin explain, Nichols “had supervision of the research and development connected with, and the design, construction, and operation of, all plants required to produce plutonium-239 and uranium-235, including the construction of the towns of Oak Ridge, Tennessee, and Richland, Washington. The responsibility of his position was massive as he oversaw a workforce of both military and civilian personnel of approximately 125,000; his Oak Ridge office became the center of the wartime atomic energy’s activities.”
Shawn D. Pautz, Tara M. Pandya, Marvin L. Adams
Nuclear Science and Engineering | Volume 169 | Number 3 | November 2011 | Pages 245-261
Technical Paper | doi.org/10.13182/NSE10-30
Articles are hosted by Taylor and Francis Online.
The well-known “sweep” algorithm for inverting the streaming-plus-collision term in first-order deterministic radiation transport calculations suffers from parallel scaling issues caused by a lack of concurrency in the spatial dimension along the direction of particle travel. We investigate a new class of parallel algorithms that involves recasting the streaming-plus-collision problem in prefix form and solving via cyclic reduction. This method, although computationally more expensive at low levels of parallelism than the sweep algorithm, offers better theoretical scalability properties. Previous work has demonstrated this approach for one-dimensional calculations; we show how to extend it to multidimensional calculations. Notably, for multiple dimensions it appears that this approach is limited to long-characteristics discretizations; other discretizations cannot be cast in practical prefix form. Computational results on two different massively parallel computer systems demonstrate that both our “forward” and “symmetric” algorithms behave similarly, scaling well to larger degrees of parallelism than sweep-based solvers. We do observe some issues at the highest levels of parallelism (relative to the computer system size) and discuss possible causes. We conclude that this approach shows good potential for future parallel systems but that parallel scalability will depend on the architecture of the communication networks of these systems.