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
Human Factors, Instrumentation & Controls
Improving task performance, system reliability, system and personnel safety, efficiency, and effectiveness are the division's main objectives. Its major areas of interest include task design, procedures, training, instrument and control layout and placement, stress control, anthropometrics, psychological input, and motivation.
Meeting Spotlight
Utility Working Conference and Vendor Technology Expo (UWC 2024)
August 4–7, 2024
Marco Island, FL|JW Marriott Marco Island
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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Nuclear Science and Engineering
September 2024
Nuclear Technology
August 2024
Fusion Science and Technology
Latest News
Taking shape: Fusion energy ecosystems built with public-private partnerships
It’s possible to describe fusion in simple terms: heat and squeeze small atoms to get abundant clean energy. But there’s nothing simple about getting fusion ready for the grid.
Private developers, national lab and university researchers, suppliers, and end users working toward that goal are developing a range of complex technologies to reach fusion temperatures and pressures, confounded by science and technology gaps linked to plasma behavior; materials, diagnostics, and electronics for extreme environments; fuel cycle sustainability; and economics.
Christopher M. Ryan, Craig M. Marianno, William S. Charlton, Alexander A. Solodov, Ronald J. Livesay, Braden Goddard
Nuclear Technology | Volume 186 | Number 3 | June 2014 | Pages 415-426
Technical Paper | Radiation Transport and Protection | doi.org/10.13182/NT13-98
Articles are hosted by Taylor and Francis Online.
The collapse of the Soviet Union ushered in an era of interest in the security of the radiological and nuclear material holdings of the Russian Federation and other countries of the Former Soviet Union. Additionally, the increasing sophistication of international criminal and terrorist organizations highlighted the need to secure these materials and prevent them from being smuggled from their point of origin and across international boundaries. To combat the growing threat of radiological and nuclear smuggling, radiation portal monitors (RPMs) are deployed at ports of entry (POEs) around the world to passively detect gamma and neutron radiation signatures from cargo and pedestrian traffic. In some locations, RPMs are reporting abnormally high gamma-ray background count rates, a situation that has been attributed, in part, to the building materials surrounding the RPMs. The primary objective of this work was to determine the impact of different types of concrete on the gamma-ray background readings in a particular RPM. Secondary objectives include developing an adaptable model to estimate the gamma-ray background contribution from any composition of concrete in any RPM configuration and determining the elemental composition of different concrete samples through neutron activation analysis (NAA) techniques. The specific activities of 40K and isotopes from the 238U and 232Th decay series were determined with a high-purity germanium detector and computer-generated calibration files. Through NAA, 34 elemental compositions were determined for six concrete samples from three different parent slabs. The total weight percentages determined were 84% to 100% of the total mass of the samples. The Monte Carlo N-Particle (MCNP) transport code was used to simulate the RPM response to the different concrete slabs. The MCNP model was validated by comparing actual and simulated detector responses to 137Cs check sources of varying strengths. For all validation cases, the MCNP estimates were 6% to 16% less than the value obtained from the actual RPM data. This work shows that it is possible to estimate the gamma-ray response of an RPM to the underlying concrete roadway. Knowing the amount of this contribution will allow RPM customers to choose suitable foundation materials before installation and accurately set alarm thresholds. This could ultimately increase the ability of RPMs to detect radiation at POEs, thereby increasing the probability of a seizure of smuggled radiological and nuclear materials.