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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.
A. D’Angelo,A. Filip
Nuclear Science and Engineering | Volume 114 | Number 4 | August 1993 | Pages 332-341
Technical Paper | doi.org/10.13182/NSE93-A24042
Articles are hosted by Taylor and Francis Online.
The uncertainty of the 235U, 239Pu, and 238U absolute delayed neutron yields vd is one of the principal sources of uncertainty in predicting the fission reactor reactivity scale βeff. The current uncertainties in the dependence of vd on incident neutron energy is investigated for significance in the evaluation of βeff. The uncertainty effects on the GODIVA, JEZEBEL, Zero Power Reactor, SNEAK, and Masurca benchmark facility calculations are analyzed using ENDF/B and JEF basic data. Different assumptions about the energy dependence result in variations of up to 5% in the reactor spectrum averaged values of vd, and these would result in variations of up to ∼2% in the value of βeff for a typical liquid-metal fast breeder reactor.
