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Education, Training & Workforce Development
The Education, Training & Workforce Development Division provides communication among the academic, industrial, and governmental communities through the exchange of views and information on matters related to education, training and workforce development in nuclear and radiological science, engineering, and technology. Industry leaders, education and training professionals, and interested students work together through Society-sponsored meetings and publications, to enrich their professional development, to educate the general public, and to advance nuclear and radiological science and engineering.
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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.”
K. D. Lathrop
Nuclear Science and Engineering | Volume 119 | Number 1 | January 1995 | Pages 80-86
Technical Notes | doi.org/10.13182/NSE95-A24071
Articles are hosted by Taylor and Francis Online.
The cosine of the laboratory scattering angle is derived for a neutron elastically scattering from a nucleus moving with a specified velocity. Scattering is assumed to be isotropic in the center-of-mass system, and the mean cosine of the laboratory scattering angle is calculated and shown to agree with the first Legendre moment of a scattering probability function derived by Blackshaw and Murray. Isotropic neutron-nucleus encounters are further assumed, and a second average is taken to calculate a mean cosine as a function of the neutron-nuclear speed ratio. This mean cosine approaches 2/(3m), where m is the nucleus mass relative to the neutron mass, as the neutron speed becomes large compared with the speed of the nucleus, but for m > 1, the scattering becomes more anisotropic as this speed ratio decreases before approaching isotropy at small neutron-nucleus speed ratios. This single nuclear speed mean cosine is compared with its average over a Maxwellian distribution of nuclear speeds. The two are qualitatively very similar. Taking the single nuclear speed to be the average speed of the Maxwellian distribution gives better quantitative agreement, in a least-squares sense, between the single-speed mean cosine and the Maxwellian average mean cosine than does using the most probable speed of the Maxwellian distribution.