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
2026 Annual Conference
May 31–June 3, 2026
Denver, CO|Sheraton Denver
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
Dec 2025
Jul 2025
Latest Journal Issues
Nuclear Science and Engineering
January 2026
Nuclear Technology
December 2025
Fusion Science and Technology
November 2025
Latest News
Bechtel-led SIMCO awarded three-year WIPP contract extension
The Department of Energy has issued a three-year contract extension to Salado Isolation Mining Contractors (SIMCO), a single-purpose entity comprising Bechtel National and Los Alamos Technical Associates as a teaming contractor, for the continued management and operations of the Waste Isolation Pilot Plant, the DOE’s geologic repository for defense-generated transuranic waste in southeastern New Mexico.
L. P. Geraldo, L. A. Vinhas, M. T. F. Cesar
Nuclear Science and Engineering | Volume 89 | Number 2 | February 1985 | Pages 150-158
Technical Paper | doi.org/10.13182/NSE85-A18189
Articles are hosted by Taylor and Francis Online.
The photodisintegration of 237Np has been studied using monochromatic photons produced by thermal neutron capture in several materials. The partial cross sections σγ, f and σγ, n were measured in the energy interval from 5.43 to 10.83 MeV. Analyzing the photofission data according to the liquid drop model, the height (Ef) and the curvature (ℏω) of the simple fission barrier were determined: Ef = (5.9 ± 0.2) MeV and ℏ;ω = (0.8 ± 0.4) MeV. For the competition between photoneutron emission and fission (Γn/Γf), a constant value was found (1.28 ± 0.15) in the 6.73- to 10.83-MeV energy range. From this result the following nuclear temperatures for 237Np were extracted on bases of some models of level density: T = 0.84 ± 0.06 MeV (Fujimoto-Yamaguchi model) and T = 0.60 ± 0.04 MeV (constant nuclear temperature model).