ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
Explore the many uses for nuclear science and its impact on energy, the environment, healthcare, food, and more.
Explore membership for yourself or for your organization.
Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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!
Latest Magazine Issues
Aug 2025
Jan 2025
Latest Journal Issues
Nuclear Science and Engineering
September 2025
Nuclear Technology
Fusion Science and Technology
August 2025
Latest News
DOE fast tracks test reactor projects: What to know
The Department of Energy today unveiled 10 companies racing to bring test reactors online by next year to meet Trump's deadline of next Independance Day, leveraging a new DOE pathway that allows reactor authorization outside national labs. As first outlined in one of the four executive orders on nuclear energy released by President Trump on May 23 and in the request for applications for the Reactor Pilot Program released June 18, the companies must use their own money and sites—and DOE authorization—to get reactors operating. What they won’t need is a Nuclear Regulatory Commission license.
W. Krappel, H. Seufert, D. Stegemann
Nuclear Technology | Volume 12 | Number 2 | October 1971 | Pages 226-234
Technical Paper | Analysis | doi.org/10.13182/NT71-A31030
Articles are hosted by Taylor and Francis Online.
The 140Ba cumulative yield of irradiated uranium has been determined absolutely by a nondestructive method. Thin uranium foils are irradiated in the fast thermal zero-power reactor STARK. To avoid radiochemical separation, the 1596.5-keV gamma activity of 140La, the daughter nucleus of 140Ba, is measured with a high resolution (2.6 keV fwhm) Ge (Li) detector. From this 140La activity the absolute 140Ba yield is evaluated from the corresponding absolute fission rate and. the detector efficiency known for the 1596.5-keV photopeak. The uranium fission rate in the foil is normalized to the absolute fission rate measured with a calibrated parallel-plate chamber. Calibration of the gamma spectrometer is performed with activated thin La2O3 foils whose absolute activities are determined by 2π beta counting. The 140Ba cumulative yield data obtained are 6.29 ± 0.14% for 235 U thermal neutron fission and 6.10 ± 0.15(%) and 6.34 ± 0.41(%) for fast neutron fission of 235U and 238U, respectively. They are in good agreement (within ±1%) with the values reported to date.
