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Radiation Protection & Shielding
The Radiation Protection and Shielding Division is developing and promoting radiation protection and shielding aspects of nuclear science and technology — including interaction of nuclear radiation with materials and biological systems, instruments and techniques for the measurement of nuclear radiation fields, and radiation shield design and evaluation.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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February 2025
Latest News
WEST claims latest plasma confinement record
The French magnetic confinement fusion tokamak known as WEST maintained a plasma in February for more than 22 minutes—1,337 seconds, to be precise—and “smashed” the previous record plasma duration for a tokamak with a 25 percent improvement, according to the CEA, which operates the machine. The previous 1,006-second record was set by China’s EAST just a few weeks prior. Records are made to be broken, but this rapid progress illustrates a collective, global increase in plasma confinement expertise, aided by tungsten in key components.
R. D. Lawrence, J. J. Dorning
Nuclear Science and Engineering | Volume 64 | Number 2 | October 1977 | Pages 492-507
Technical Paper | doi.org/10.13182/NSE77-A27385
Articles are hosted by Taylor and Francis Online.
A smoothing and extrapolation method is applied to the point kinetics equations and the one-dimensional space-dependent reactor kinetics equations. The simple smoothing procedure is shown to be very efficient in reducing the oscillatory errors that occur when the standard Padé(1,1) and Crank-Nicholson approximations are applied to stiff reactor kinetics equations. Fourth-order accuracy is achieved by applying a single Richardson extrapolation (on a global basis) to the smoothed results obtained from values calculated using two time-step grids. The numerical results for point kinetics demonstrate that the method is particularly efficient for very stiff problems such as subcritical and delayed supercritical transients in fast reactors. Application of the method to two one-dimensional kinetics benchmark problems solved using a standard space-dependent computer code that utilizes the Crank-Nicholson approximation leads to significant reduction in the overall computational effort required to achieve a given accuracy.