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Fusion Energy
This division promotes the development and timely introduction of fusion energy as a sustainable energy source with favorable economic, environmental, and safety attributes. The division cooperates with other organizations on common issues of multidisciplinary fusion science and technology, conducts professional meetings, and disseminates technical information in support of these goals. Members focus on the assessment and resolution of critical developmental issues for practical fusion energy applications.
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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.”
M. T. Andrews, J. T. Goorley, E. C. Corcoran, D. G. Kelly
Nuclear Technology | Volume 187 | Number 3 | September 2014 | Pages 235-242
Technical Paper | Fission Reactors | doi.org/10.13182/NT13-72
Articles are hosted by Taylor and Francis Online.
Study of the magnitude and temporal behavior of delayed neutrons (DNs) enables the identification of fissile isotopes and a determination of their relative quantities. Thus, the ability to model accurately these neutrons and the methods of their detection is of relevance to nuclear forensics and counterterrorism. The capability of MCNP6 to model these emissions was examined and compared to measurements of the DNs produced by 233U, 235U, and 239Pu after neutron-induced fission. Fissile samples were irradiated in a SLOWPOKE-2 research reactor for 60 s and were then conveyed via pneumatic tubing to an array of six 3He detectors embedded in a paraffin moderator. Several MCNP6 input files were created to reproduce irradiation conditions, temporal DN emission, and the detection arrangement. Nuclear reactions and other effects within the 3He detectors were reproduced by MCNP6, and detection efficiencies of this modeled arrangement determined by MCNP6 were in agreement with experimental measurements. Finally, the library and model DN emission options in the MCNP6v1 release were evaluated and compared to the measured magnitudes and temporal behavior of 233U, 235U, and 239Pu. Significant discrepancies observed between the DN model option and measurements for count times >100 s are discussed.
