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Radiation Protection & Shielding
The Radiation Protection and Shielding Division is developing and promoting radiation protection and shielding aspects of nuclear science and technology — including interaction of nuclear radiation with materials and biological systems, instruments and techniques for the measurement of nuclear radiation fields, and radiation shield design and evaluation.
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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.”
E. F. Seleznev, V. Bereznev, I. Chernova
Nuclear Science and Engineering | Volume 193 | Number 5 | May 2019 | Pages 495-505
Technical Paper | doi.org/10.1080/00295639.2018.1542866
Articles are hosted by Taylor and Francis Online.
This paper proposes partial neutron transport equations for stationary and transient calculations. The partial equations of neutron transport are based on separately following neutrons born from external source, prompt fission neutrons, and delayed neutrons. The delayed neutrons are described by a system of equations containing one equation for each group. The paper defines the parameters of these equations and presents the results of fast neutron reactor benchmark calculations.
Determination of the field of the external source neutrons in the system of partial equations provides a natural transfer of the source power (in units of neutrons per second) to the core power of energy release from the interaction of the external source neutrons in the reactor core (in units of watt). Thus, an external source neutron is used for the initial normalization of the neutron field based on the required reactor power. Operating with the field of delayed neutrons, in contrast to the field of concentrations of delayed neutron precursors, provides a quantitative assessment of the interaction of these neutrons with the reactor environment, and thus, assesses their contribution to the reactivity effects in fast reactors.
Partial neutron transport equations allow us to extract additional information about the time behavior of the fast neutron reactor.