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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
Standards Program
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.
Robert Conn, Mohamed Sawan
Nuclear Science and Engineering | Volume 48 | Number 3 | July 1972 | Pages 361-366
Technical Note | doi.org/10.13182/NSE72-A22495
Articles are hosted by Taylor and Francis Online.
The analysis of the slowing down of a neutron pulse leads to a detailed analogy between the decay of a pulse in the fast regime versus the decay in the thermal energy region. It is found that the slope, α, of log N(t) versus log(t) depends on the system buckling, B2. An “α versus B2” curve exists that is analogous to the “λ versus B2” curve for thermal systems. Other analogies between fast and thermal time decay are discussed. These analogies exist despite the fact that no time eigenvalue exists for this slowing down problem.
