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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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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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Proving DRACO will deliver
The United States is now closer than it has been in over five decades to launching the first nuclear thermal rocket into space, thanks to DRACO—the Demonstration Rocket for Agile Cislunar Orbit.
Brian R. Nease, Taro Ueki
Nuclear Science and Engineering | Volume 157 | Number 1 | September 2007 | Pages 51-64
Technical Paper | doi.org/10.13182/NSE07-A2712
Articles are hosted by Taylor and Francis Online.
A coarse-mesh projection method has been developed for the Monte Carlo calculation of dominant eigenvalue ratio [dominance ratio (DR)]. The first step of the method consists of the regression analysis of the multivariate time series from the coarse-mesh binning of the Monte Carlo fission source distribution. The second step is computation of the eigenvectors of the adjoint matrix of noise propagation. In general, projections on these eigenvectors can be utilized to compute important characteristics of the eigenmodes of fission source distribution. In this work, it has been proven that if the eigenvector corresponding to the largest eigenvalue of the aforementioned adjoint matrix is taken to be the vector for projection, the projected scalar time series follows the autoregressive process of order one with the root of characteristic polynomial, i.e., the autocorrelation coefficient, being the DR of fission source distribution. Numerical results are presented for four problems including one-energy-group checkerboard-type problems, a one-energy-group cube problem and a continuous-energy pressurized water reactor core problem. The strength of the method is twofold; (a) the elimination of the use of autoregressive moving average fitting, and (b) no need to optimize the order of fitting.