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 Nuclear Energy Conference & Expo (NECX)
August 24–27, 2026
Dallas, TX|Hilton Anatole
Latest Magazine Issues
Jul 2026
Jan 2026
2026
Latest Journal Issues
Nuclear Science and Engineering
August 2026
Nuclear Technology
July 2026
Fusion Science and Technology
Latest News
The deadline arrives: Checking in on the Reactor Pilot Program
On May 23, 2025, President Trump signed Executive Order 14301, “Reforming Nuclear Reactor Testing at the DOE,” which instructed the Department of Energy to create a Reactor Pilot Program (RPP)—a new system in which companies could pursue DOE authorization to build and test their first-of-a-kind nuclear technologies. EO 14301 set an ambitious goal for that program: three reactors achieving criticality by July 4, 2026.
R. T. Santoro, R. G. Alsmiller, Jr., J. M. Barnes, G. T. Chapman, J. S. Tang
Nuclear Science and Engineering | Volume 80 | Number 4 | April 1982 | Pages 586-602
Technical Paper | doi.org/10.13182/NSE82-A18972
Articles are hosted by Taylor and Francis Online.
Integral experiments that measure the streaming of ∼14-MeV neutrons through a 0.30-m-diam iron duct (length-to-diameter ratio ∼ 3) imbedded in a concrete shield have been carried out at the Oak Ridge National Laboratory. Calculated and measured neutron and gamma-ray energy spectra are compared at 16 detector locations on and off the cylindrical axis of the duct. The measured spectra were obtained using an NE-213 liquid scintillator detector with pulse-shape discrimination to simultaneously resolve neutron and gamma-ray events. The calculated spectra were obtained using a computer code network that incorporates two radiation transport methods: discrete ordinates (with P3 multigroup cross sections) and Monte Carlo (with continuous point cross sections). The two radiation transport methodologies are required to properly account for neutrons that single scatter from the duct to the detector. The calculated and measured outgoing neutron energy spectra above 850 keV agree within 5 to 50% depending on detector location and neutron energy. The calculated and measured gamma-ray spectra above 750 ke V are also in favorable agreement, ∼5 to 50%, depending on detector location and gamma-ray energy.