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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.
E. Neymotin
Nuclear Science and Engineering | Volume 75 | Number 2 | August 1980 | Pages 133-139
Technical Paper | doi.org/10.13182/NSE80-A21302
Articles are hosted by Taylor and Francis Online.
An approximate form of the transport equation is used to investigate stationary and time-dependent neutron slowing down and propagation in the field of gravity. The approximation is based on the expansion of the δ function of the transfer function in a power series of a small parameter s, the ratio of the neutron to atom masses. It is shown that the s and s2 approximations in the stationary neutron slowing down problems are connected with Wigner and Grueling-Goertzel approximations. A simple formula is given for time-dependent neutron slowing down. The influence of the field of gravity on the operation of a reactor and on the propagation of ultra cold neutrons is studied in the point-energy approximation. Also investigated is the neutron space-energy distribution in the field of gravity.
