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2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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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.
Paul Goldhagen
Nuclear Technology | Volume 175 | Number 1 | July 2011 | Pages 81-88
Technical Paper | Special Issue on the 16th Biennial Topical Meeting of the Radiation Protection and Shielding Division / Radiation Measurements and General Instrumentation | doi.org/10.13182/NT11-A12274
Articles are hosted by Taylor and Francis Online.
This paper describes the design and construction of an extended-range multisphere neutron spectrometer (ERMNS), also called a Bonner sphere spectrometer, created to measure the spectrum of cosmic-ray-induced neutrons on container ships. Such measurements require a highly sensitive neutron spectrometer and can benefit from improved energy resolution. To obtain high sensitivity, spherical 3 He gas proportional counters with a diameter of 152 mm (6 in.) were developed and used. The goal for designing the moderator assemblies of the new ERMNS was to optimize its energy resolution where it is typically worst for such spectrometers - at high and medium-low energies. Absorber shells containing boron carbide were used to improve resolution at medium-low energies. The response functions of various sizes and designs of plain and modified spheres were calculated using the radiation transport code MCNPX 2.6b. The resolution of combinations of 16 spheres of candidate designs was then determined using Reginatto's RESPOW code, and the sphere designs that gave the smallest standard deviations of the RESPOW averaging kernels were selected. Compared to an ERMNS used earlier for similar measurements, resolution improved by 7 to 17% from 10 eV to 0.1 MeV and 24 to 39% from 10 MeV to 10 GeV. Bayesian parameter estimation was also used to characterize the uncertainties in spectra measured with the old and new spectrometers. The uncertainties in the fluence rates and peak energies of a typical terrestrial cosmic-ray neutron spectrum improved by 15 to 85% and 56 to 400%, respectively. These results demonstrate the utility of RESPOW and Bayesian parameter estimation for designing ERMNSs.
