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Reactor Physics
The division's objectives are to promote the advancement of knowledge and understanding of the fundamental physical phenomena characterizing nuclear reactors and other nuclear systems. The division encourages research and disseminates information through meetings and publications. Areas of technical interest include nuclear data, particle interactions and transport, reactor and nuclear systems analysis, methods, design, validation and operating experience and standards. The Wigner Award heads the awards program.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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.”
William H. Miller, Walter Meyer, Darrol H. Timmons
Nuclear Science and Engineering | Volume 62 | Number 2 | February 1977 | Pages 262-269
Technical Paper | doi.org/10.13182/NSE77-A26961
Articles are hosted by Taylor and Francis Online.
Fast-neutron angular penetration spectra were experimentally determined for a fast-neutron spectrum incident on 4-, 8-, and 12-in. (102-, 203-, and 305-mm)-thick water slabs. The experimental spectra were compared with MORSE Monte Carlo calculations using readily available multigroup cross sections. The source of fast neutrons for the experimental study was the Missouri University Research Reactor; the incident and penetration neutron spectra were detected using a 2- X 2-in. (51- X 51-mm) NE-213 liquid scintillation spectrometer system. A comparison of the Monte Carlo and experimental results showed excellent agreement for all but the thickest slabs. All results showed similar trends and structure, and only for the 12-in. slab did the experimental and calculated result vary by as much as 40% for shallow angle penetrations. Integrated spectral results are generally within ±15% for all reported angles and thicknesses. A modification to the well-known MORSE code has been utilized to calculate group-to-group transfer probabilities for each of the experimental geometries. These probabilities have been converted to dose and are tabulated to permit calculation of the penetration dose for any incident neutron spectrum for the comprehensive set of angles considered in this work.