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.
R. L. French, L. G. Mooney
Nuclear Technology | Volume 10 | Number 3 | March 1971 | Pages 348-365
Technical Paper | Radiation | doi.org/10.13182/NT71-A30969
Articles are hosted by Taylor and Francis Online.
Techniques were developed for applying the results of Straker’s recent discrete ordinates calculations of neutron transport in an air-over-ground geometry to predict the neutron -radiation environment produced by the detonation of nuclear weapons. Straker’s results include the spatial, energy, and angle distributions of neutrons at the air-ground interface from source neutrons in each of nine source-energy bands emitted from a point isotropic source 50 ft above the ground. The source-energy bands cover the range from 0.0033 to 15.0 MeV. The energy spectrum of the leakage neutrons from a particular weapon may be integrated over corresponding energy bands toob-tain source intensities which are then multiplied by the transport data for corresponding bands and summed over source energy. The results thus obtained are for Straker’s original air density of 1.1 x 10-3 g/cm3, but they may be sealed to other air densities by use of mass equivalent ranges. A satisfactory adjustment to source heights other than the 50-ft height used in the original calculations may be made with the “first-last collision method” if the source-detector separation is as much as 2 or 3 mean-free-paths (∼1000 ft). When folded with leakage spectra for numerous test devices and adjusted to the proper air density and burst height, Straker’s data give neutron-dose spatial distributions generally within 25% of those measured infield tests.