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Division Spotlight
Robotics & Remote Systems
The Mission of the Robotics and Remote Systems Division is to promote the development and application of immersive simulation, robotics, and remote systems for hazardous environments for the purpose of reducing hazardous exposure to individuals, reducing environmental hazards and reducing the cost of performing work.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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Latest News
First astatine-labeled compound shipped in the U.S.
The Department of Energy’s National Isotope Development Center (NIDC) on March 31 announced the successful long-distance shipment in the United States of a biologically active compound labeled with the medical radioisotope astatine-211 (At-211). Because previous shipments have included only the “bare” isotope, the NIDC has described the development as “unleashing medical innovation.”
Reuben T. Sorensen, John C. Lee
Nuclear Science and Engineering | Volume 158 | Number 3 | March 2008 | Pages 213-230
Technical Paper | doi.org/10.13182/NSE08-A2749
Articles are hosted by Taylor and Francis Online.
We have developed a light water reactor (LWR) equilibrium cycle search algorithm that is similar to the REBUS-3 fast reactor methodology but with depletion capabilities typically employed for LWR analysis. Our LWR methodology projects the original coupled nonlinear isotopic balance equations to a series of equations that are piecewise linear in time. Iterations are performed on microscopic reaction rates until the linearized isotopic balance equations yield an ultimate equilibrium state. We further reduce the computational burden associated with LWR analysis by approximating global depletion calculations with assembly-level, collision probability calculations performed by the CASMO-3 code. We demonstrate the benefits of our equilibrium cycle methodology by calculating the true equilibrium Pu inventory of two configurations: a heterogeneous assembly configuration that contains both low enriched UO2 and mixed oxide (MOX) fuel pins and a homogeneous configuration comprising a 2 × 2 colorset arrangement of MOX and low enriched UO2 assemblies. For each configuration our methodology yields a true equilibrium Pu inventory with only 12 CASMO-3 lattice physics calculations. As a validation, an inventory extrapolation technique is used to arrive at a quasi-equilibrium cycle for both LWR configurations. The extrapolated technique yields a similar Pu inventory and isotopic composition but requires 65 lattice physics calculations.