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.
Shun-ichi Tanaka, Kiyoshi Takeuchi
Nuclear Science and Engineering | Volume 93 | Number 4 | August 1986 | Pages 376-385
Technical Paper | doi.org/10.13182/NSE86-A18473
Articles are hosted by Taylor and Francis Online.
Detailed calculations of the buildup factors and spectra of gamma rays including fluorescence radiations in lead are carried out using a discrete ordinates code, PALLAS-PL,SP-Br. The exposure and absorbed dose buildup factors with and without fluorescence are tabulated for 11 source energies from 0.09 to 0.3 MeV for penetration depths up to 40 mfp. Important characteristics of the gamma-ray transport in the vicinity of the K edge of lead are explored using detailed energy spectra in the medium. The contribution of the fluorescence to buildup factors is extremely significant for the sources close to the K edge energy.