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Accelerator Applications
The division was organized to promote the advancement of knowledge of the use of particle accelerator technologies for nuclear and other applications. It focuses on production of neutrons and other particles, utilization of these particles for scientific or industrial purposes, such as the production or destruction of radionuclides significant to energy, medicine, defense or other endeavors, as well as imaging and diagnostics.
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2024 ANS Annual Conference
June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
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Latest News
Zap Energy hits 37-million-degree electron temperatures in compact fusion device
Zap Energy announced April 23 that it has reached 1-3 keV plasma electron temperatures—roughly the equivalent of 11 to 37 million degrees Celsius—using its sheared-flow-stabilized Z-pinch approach to fusion. Reaching temperatures above that of the sun’s core (which is 10 million degrees Celsius temperature) is just one hurdle required before any fusion confinement concept can realistically pursue net gain and fusion energy.
E. Dumonteil, C. M. Diop
Nuclear Science and Engineering | Volume 167 | Number 2 | February 2011 | Pages 165-170
Technical Paper | doi.org/10.13182/NSE09-100
Articles are hosted by Taylor and Francis Online.
External linking scripts between Monte Carlo transport codes and burnup codes, and complete integration of burnup capability into Monte Carlo transport codes, have been or are currently being developed. Monte Carlo-linked burnup methodologies may serve as an excellent benchmark for new deterministic burnup codes used for advanced systems; however, there are some instances where deterministic methodologies break down (i.e., heavily angularly biased systems containing exotic materials without proper group structure) and Monte Carlo burnup may serve as an actual design tool. Therefore, researchers are also developing these capabilities in order to examine complex, three-dimensional exotic material systems that do not contain benchmark data.Providing a reference scheme implies being able to associate statistical errors to any neutronic value of interest like keff, reaction rates, fluxes, etc. Usually in Monte Carlo, standard deviations are associated with a particular value by performing different independent and identical simulations (also referred to as “cycles,” “batches,” or “replicas”), but this is only valid if the calculation itself is not biased. And, as will be shown in this paper, there is a bias in the methodology that consists of coupling transport and depletion codes because Bateman equations are not linear functions of the fluxes or of the reaction rates (those quantities being always measured with an uncertainty). Therefore, we have to quantify and correct this bias. This will be achieved by deriving an unbiased minimum variance estimator of a matrix exponential function of a normal mean. The result is then used to propose a reference scheme to solve Boltzmann/Bateman coupled equations, thanks to Monte Carlo transport codes. Numerical tests will be performed with an ad hoc Monte Carlo code on a very simple depletion case and will be compared to the theoretical results obtained with the reference scheme. Finally, the statistical error propagation during the time-dependent depletion process will be discussed. It will be proven that the nonlinearity of Bateman equations induces a bias in the coupling. The paper provides a formula to correct it, which is verified in a simple example.