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Division Spotlight
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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2025 ANS Annual Conference
June 15–18, 2025
Chicago, IL|Chicago Marriott Downtown
Standards Program
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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Smarter waste strategies: Helping deliver on the promise of advanced nuclear
At COP28, held in Dubai in 2023, a clear consensus emerged: Nuclear energy must be a cornerstone of the global clean energy transition. With electricity demand projected to soar as we decarbonize not just power but also industry, transport, and heat, the case for new nuclear is compelling. More than 20 countries committed to tripling global nuclear capacity by 2050. In the United States alone, the Department of Energy forecasts that the country’s current nuclear capacity could more than triple, adding 200 GW of new nuclear to the existing 95 GW by mid-century.
Hideo Hirayama
Nuclear Technology | Volume 77 | Number 1 | April 1987 | Pages 60-67
Technical Paper | Radioisotopes and Isotope Separation | doi.org/10.13182/NT87-A33952
Articles are hosted by Taylor and Francis Online.
Exposure buildup factors for plane normal sources have been calculated with an electron gamma shower Monte Carlo code, EGS4, for water, concrete, iron, and lead in the 10 to 100 MeV range. Electron reactions like multiple scattering, collision, and continuous energy loss are taken into account together with bremsstrahlung. The buildup factors in this energy region are affected very much by the energy loss mechanism of electrons and positrons in the medium. The energy of electrons or positrons in lead is mainly converted to photons via the bremsstrahlung reaction; therefore, buildup factors increase rapidly with the increase of the photon energy. In the case of water, the energy of electrons or positrons is mainly spent in ionization or excitation. Buildup factors for water decrease gradually to 40 MeV and increase gradually above that energy. The buildup factors in each medium are calculated for eight-source energy from 10 to 100 MeV for penetration depths as great as 10 mfp.
