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.
Division Spotlight
Fuel Cycle & Waste Management
Devoted to all aspects of the nuclear fuel cycle including waste management, worldwide. Division specific areas of interest and involvement include uranium conversion and enrichment; fuel fabrication, management (in-core and ex-core) and recycle; transportation; safeguards; high-level, low-level and mixed waste management and disposal; public policy and program management; decontamination and decommissioning environmental restoration; and excess weapons materials disposition.
Meeting Spotlight
Conference on Nuclear Training and Education: A Biennial International Forum (CONTE 2025)
February 3–6, 2025
Amelia Island, FL|Omni Amelia Island Resort
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!
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Christmas Night
Twas the night before Christmas when all through the houseNo electrons were flowing through even my mouse.
All devices were plugged in by the chimney with careWith the hope that St. Nikola Tesla would share.
Z. D. Whetstone, K. J. Kearfott
Nuclear Technology | Volume 176 | Number 3 | December 2011 | Pages 395-413
Technical Paper | Radiation Transport and Protection | doi.org/10.13182/NT10-118
Articles are hosted by Taylor and Francis Online.
This research was conducted to determine the optimal way to shield a compact, isotropic neutron source into a beam for active interrogation neutron systems. To define the restricted emission angle and to protect nearby personnel when stand-off distances are limited, shielding materials were added around the source. Because of limited space in many locations where active neutron interrogation is employed, a compact yet effective design was desired. Using the Monte Carlo N-Particle Transport Code, several shielding geometries were modeled. Materials investigated were polyethylene, polyethylene enriched with 10B, water, bismuth, steel, nickel, INCONEL® alloy 600, tungsten, lead, and depleted uranium. Various simulations were run testing the individual materials and combinations of them. It was found that at a stand-off distance of 1.5 m from the source, the most effective shielding configuration is a combination of several layers of polyethylene and steel. Without any shielding, the dose is 3.71 × 10-15 Sv/source particle. With a shielding consisting of multiple layers of steel totaling 30 cm thickness interspersed with several layers of polyethylene totaling 20 cm thickness, the dose drops to 3.68 × 10-17 Sv/emitted neutron at radians opposite the shield opening. The layered shielding approach is more effective at reducing dose equivalent and neutron fluence than shields made out of single continuous layers of the same material and thicknesses. Adding boron to the polyethylene and substituting tungsten for steel would make the shielding more effective but would add mass and cost.