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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 RAIN scale: A good intention that falls short
Radiation protection specialists agree that clear communication of radiation risks remains a vexing challenge that cannot be solved solely by finding new ways to convey technical information.
Earlier this year, an article in Nuclear News described a new radiation risk communication tool, known as the Radiation Index, or, RAIN (“Let it RAIN: A new approach to radiation communication,” NN, Jan. 2025, p. 36). The authors of the article created the RAIN scale to improve radiation risk communication to the general public who are not well-versed in important aspects of radiation exposures, including radiation dose quantities, units, and values; associated health consequences; and the benefits derived from radiation exposures.
Noel Corngold
Nuclear Science and Engineering | Volume 102 | Number 1 | May 1989 | Pages 114-118
Technical Note | doi.org/10.13182/NSE89-A23635
Articles are hosted by Taylor and Francis Online.
The time-dependent slowing down of neutrons in noncapturing media depends in an important way on how the energy-dependent mean-free-time between scatterings behaves as E → 0. For example, if the mean-free-time decreases, i.e., ν∑s increases, as any positive power of E, the integrated density of neutrons does not remain constant in time. This anomalous behavior is discussed, noting both analogies in other physical processes and early references to the phenomenon of “nonconservation.” The analysis uses some unfamiliar solutions for slowing down in hydrogen, when the cross section has power-law variation; however, the general discussion is not limited to the equal mass case.