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
New coolants, new fuels: A new generation of university reactors
Here’s an easy way to make aging U.S. power reactors look relatively youthful: Compare them (average age: 43) with the nation’s university research reactors. The 25 operating today have been licensed for an average of about 58 years.
R. L. Macklin, J. Halperin
Nuclear Science and Engineering | Volume 64 | Number 4 | December 1977 | Pages 849-858
Technical Paper | doi.org/10.13182/NSE77-A14500
Articles are hosted by Taylor and Francis Online.
Neutron capture by isotopically purified 232Th was measured at the Oak Ridge Electron Linear Accelerator. The pulse-height weighting method was used with small liquid scintillators to measure the prompt gamma-ray energy release following neutron capture. Resonance parameters were derived up to 10 keV. The average radiative width was (19.8 ± 0.2 statistical ± 0.4 systematic) meV for 50 resonances in the 2.6- to 4.0-keV interval. Strength functions 104S0 = 0.365 ± 0.024, 104 S1 = 1.078 ± 0.057, 104S2 > 0.842 ± 0.084, and y/D0 = 0.0198/(13.24 ± 0.71) were found to fit the average cross section well (to 105 keV) when allowance was made for p-wave inelastic competition above the ∼50-keV threshold. While the values stated gave the best fit (from 2.6 to 105 keV) when all four were allowed to vary, it is likely that “acceptable” fits could be forced for other values. Recent evaluations of the cross section range from 8 to 50% higher than results reported here.