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Aerospace Nuclear Science & Technology
Organized to promote the advancement of knowledge in the use of nuclear science and technologies in the aerospace application. Specialized nuclear-based technologies and applications are needed to advance the state-of-the-art in aerospace design, engineering and operations to explore planetary bodies in our solar system and beyond, plus enhance the safety of air travel, especially high speed air travel. Areas of interest will include but are not limited to the creation of nuclear-based power and propulsion systems, multifunctional materials to protect humans and electronic components from atmospheric, space, and nuclear power system radiation, human factor strategies for the safety and reliable operation of nuclear power and propulsion plants by non-specialized personnel and more.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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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Latest News
Norway’s Halden reactor takes first step toward decommissioning
The government of Norway has granted the transfer of the Halden research reactor from the Institute for Energy Technology (IFE) to the state agency Norwegian Nuclear Decommissioning (NND). The 25-MWt Halden boiling water reactor operated from 1958 to 2018 and was used in the research of nuclear fuel, reactor internals, plant procedures and monitoring, and human factors.
Gregory A. Moses
Nuclear Science and Engineering | Volume 64 | Number 1 | September 1977 | Pages 49-63
Technical Paper | doi.org/10.13182/NSE77-A27076
Articles are hosted by Taylor and Francis Online.
Laser fusion hydrodynamics calculations include both the solution of the plasma hydrodynamics equations and transport equations for various nonthermal particles. The solution of the hydrodynamics equations is usually a combination of an explicit technique for the hyperbolic equation-of-motion and an implicit method for parabolic temperature equations. Transport equations are solved using fully implicit techniques to allow their time step to be as large as the time step used in the solution of the hydrodynamics equations. Multigroup flux-limited diffusion theory is often used to model the time-dependent transport problem. In this method, the diffusion coefficient is “adjusted” to provide a physically plausible result in the free streaming limit. The energy dependence of the distribution function is modeled using multigroup theory. Another method of solving the transport problem, time-dependent particle tracking, approximates the trajectory of the charged particles as straight lines, from creation to thermalization. This simple method accurately describes the slowing down of thermonuclear reaction products, while the flux-limited diffusion technique is more applicable to the transport of electrons and photons.