ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
Explore the many uses for nuclear science and its impact on energy, the environment, healthcare, food, and more.
Explore membership for yourself or for your organization.
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!
Latest Magazine Issues
Jul 2025
Jan 2025
Latest Journal Issues
Nuclear Science and Engineering
September 2025
Nuclear Technology
August 2025
Fusion Science and Technology
Latest News
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.
E. S. Hotston
Fusion Science and Technology | Volume 26 | Number 3 | November 1994 | Pages 203-221
Technical Paper | Divertor System | doi.org/10.13182/FST94-A30323
Articles are hosted by Taylor and Francis Online.
The exhaust modeling program for a fusion reactor based on a tokamak carried out for Next European Torus (NET)/International Tokamak Reactor (INTOR)/International Thermonuclear Experimental Reactor (ITER) in the years 1982 to 1991 during which the author was involved is open to criticism on at least two counts. The first is that although in general there are at least two plasma configurations in the divertor that balance the upstream plasma pressure and power flow into the divertor, only one solution was accepted. The other solutions were assumed to be nonexistent or unimportant. The second count is that the possibility was not considered that atoms backscattered from the plasma could deposit power in the divertor target; inclusion of this process would have enlarged the domain in which multiple solutions are important. In particular, a plasma in which the temperatures are low appears as a possible solution. Here the atomic and molecular properties of the fuel, which vary quite rapidly with the electron temperature, are very important, so obtaining this solution by an implicit procedure is difficult. The two-dimensional modeling programs referred to earlier were carried out with the use of the Braams plasma transport code, which relies on a “strongly implicit method” for its updating. Examination of this code shows that the techniques used to stabilize it are incompatible with the procedures required to find the low-temperature solution. These objections would remain in the case where a Monte Carlo code is used to trace the fate of the neutrals recycled in the divertor. Recent modeling work based on Monte Carlo codes suggests that the plasma temperatures of the higher temperature solutions are likely to be greater than previously thought. Thus, resolution of the problem of finding the lower temperature solutions becomes important.