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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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Deep Space: The new frontier of radiation controls
In commercial nuclear power, there has always been a deliberate tension between the regulator and the utility owner. The regulator fundamentally exists to protect the worker, and the utility, to make a profit. It is a win-win balance.
From the U.S. nuclear industry has emerged a brilliantly successful occupational nuclear safety record—largely the result of an ALARA (as low as reasonably achievable) process that has driven exposure rates down to what only a decade ago would have been considered unthinkable. In the U.S. nuclear industry, the system has accomplished an excellent, nearly seamless process that succeeds to the benefit of both employee and utility owner.
Argala Srivastava, S. B. Degweker
Nuclear Science and Engineering | Volume 179 | Number 4 | April 2015 | Pages 460-476
Technical Paper | doi.org/10.13182/NSE14-42
Articles are hosted by Taylor and Francis Online.
Analytical Green’s function–based diffusion Monte Carlo (MC) methods have been applied earlier for simulation of reactor noise experiments for measuring the degree of subcriticality in accelerator-driven systems. In this method analytical solution of the diffusion equation is used to construct the probability distribution function for neutron absorption in a medium. This method has several advantages such as speed, elegance, and exactitude but was applicable to a rather restricted class of problems, such as an infinite or bare homogeneous medium.
In the present paper, we further develop the analytical Green’s function (analytical diffusion kernel) approach to demonstrate its utility in a wider class of problems like a heterogeneous medium with the same or different diffusion coefficients. We provide mathematical and numerical proofs of the validity of certain recipes that were proposed for heterogeneous systems. We also investigate whether and to what extent the diffusion theory–based MC can be improved to give results closer to transport theory, particularly in situations wherein diffusion theory methods are otherwise inapplicable.