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Conference Spotlight
2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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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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Empowering the next generation: ANS’s newest book focuses on careers in nuclear energy
A new career guide for the nuclear energy industry is now available: The Nuclear Empowered Workforce by Earnestine Johnson. Drawing on more than 30 years of experience across 16 nuclear facilities, Johnson offers a practical, insightful look into some of the many career paths available in commercial nuclear power. To mark the release, Johnson sat down with Nuclear News for a wide-ranging conversation about her career, her motivation for writing the book, and her advice for the next generation of nuclear professionals.
When Johnson began her career at engineering services company Stone & Webster, she entered a field still reeling from the effects of the Three Mile Island incident in 1979, nearly 15 years earlier. Her hiring cohort was the first group of new engineering graduates the company had brought on since TMI, a reflection of the industry-wide pause in nuclear construction. Her first long-term assignment—at the Millstone site in Waterford, Conn., helping resolve design issues stemming from TMI—marked the beginning of a long and varied career that spanned positions across the country.
Weston M. Stacey, Jr.
Nuclear Science and Engineering | Volume 29 | Number 2 | August 1967 | Pages 254-263
Technical Paper | doi.org/10.13182/NSE67-A18535
Articles are hosted by Taylor and Francis Online.
Analytical expressions for the spatially independent spectrum and importance (adjoint) function in fast-reactor assemblies have been developed. These expressions were obtained by solving the neutron balance equation, and the equation adjoint thereto, by the method of successive approximation. Solutions obtained in this manner suggest an interpretation of the collision density in terms of the probability that a fission neutron suffers a given sequence of scattering collisions, summed over all such sequences. Similarly, the importance function is interpreted in terms of the fission-neutron production probability following a given sequence of scattering collisions, summed over all such sequences. The analytical expressions are readily evaluated using either differential or group-averaged cross-section values. Integral properties of highly enriched and dilute fast-reactor assemblies were evaluated and compared with experiment; the agreement was comparable with that obtained with multigroup calculations normally employed to evaluate such assemblies.
