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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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Latest News
First astatine-labeled compound shipped in the U.S.
The Department of Energy’s National Isotope Development Center (NIDC) on March 31 announced the successful long-distance shipment in the United States of a biologically active compound labeled with the medical radioisotope astatine-211 (At-211). Because previous shipments have included only the “bare” isotope, the NIDC has described the development as “unleashing medical innovation.”
Pinky Batheja, Feroz Ahmed, L. S. Kothari, Otohiko Aizawa
Nuclear Science and Engineering | Volume 89 | Number 4 | April 1985 | Pages 366-380
Technical Note | doi.org/10.13182/NSE85-A18629
Articles are hosted by Taylor and Francis Online.
Using diffusion theory and the eigenfunction expansion method, a detailed time-dependent study of fast neutrons has been made for three iron assemblies: infinite, 1 m3, and 0.5 m3. Various results have been obtained by taking two different source energies, namely, 14.47 and 1.0076 MeV. All the calculations have been carried out using the 50-group cross-section set of Ahmed et al. For the 1.0076-MeV source, (a) the time-dependent spectra exhibit two distinct peaks up to ∼50 ns, (b) energy variation of the mean slowing down time shows “anomalous” behavior similar to that observed by Bey non et al., and (c) the most probable time has two different values for some energy groups below ∼240 keV, in conformity with the results of White et al. The double values of (except for the 40th and 41st groups) and the “anomalous” behavior observed in cease when we take the source energy to be 14.47 MeV. Further, for all values of energy Ei, the values of both and decrease as the size of the assembly is reduced. It has been shown that in the two larger assemblies, pseudoasymptotic conditions are established in certain time intervals. It was determined that some energy groups tend to cluster and decay with the same decay constant after a certain time.