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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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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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Powering the future: How the DOE is fueling nuclear fuel cycle research and development
As global interest in nuclear energy surges, the United States must remain at the forefront of research and development to ensure national energy security, advance nuclear technologies, and promote international cooperation on safety and nonproliferation. A crucial step in achieving this is analyzing how funding and resources are allocated to better understand how to direct future research and development. The Department of Energy has spearheaded this effort by funding hundreds of research projects across the country through the Nuclear Energy University Program (NEUP). This initiative has empowered dozens of universities to collaborate toward a nuclear-friendly future.
M. L. Williams
Nuclear Science and Engineering | Volume 108 | Number 4 | August 1991 | Pages 355-383
Technical Paper | doi.org/10.13182/NSE90-33
Articles are hosted by Taylor and Francis Online.
A general theory is developed to describe the mechanism by which the response observed on a detector propagates throughout a system. The response is transferred between a particle source and the detector by special particles called contributons. The distribution in phase-space of the response carried by contributons defines a new quantity called the “response continuumwhich depends on solutions to the forward and adjoint Boltzmann equations. A transport equation for the response distribution is derived, and properties of the response continuum are discussed. The response concentration is described by the contributon response density and flux, which are used to locate regions containing large amounts of potential response contribution. The flow of response through space is described by streamlines of a vector field called the “response current.” This field is related to two new variables called the “response potential” and “vorticity,"respectively. Sample results are presented for “contributon dipole” configurations. A spherical harmonic expansion of the angular flux is given to describe directional characteristics of the response continuum. The “contributon slowing-down equation” is derived to describe the simultaneous transfer of response through space and energy. A new contributon Monte Carlo method to simulate response transport is discussed.