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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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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.
Franco Alladio, Paola Batistoni, Alessandro Mancuso
Fusion Science and Technology | Volume 22 | Number 4 | December 1992 | Pages 474-481
Alpha-Particle Special | doi.org/10.13182/FST92-A30083
Articles are hosted by Taylor and Francis Online.
The properties of alpha-particle confinement of l = 2 stellarat ors have been studied as a function of the aspect ratio (3 < R/a < 12). A collisionless orbit calculation has been performed numerically for stellarator configurations obtained by winding the helical currents on circular-cross-section tori with a constant pitch in toroidal coordinates. All the configurations studied exibit pronounced separatrixlike features that also rotate with constant pitch in toroidal coordinates. The fraction of alpha particles contained within the last closed magnetic surface rapidly increases with the aspect ratio and is >80% for R/a > 4. The escaping alpha particles cross the separatrix within narrow helical strips around the X-point path when it is between the inboard and the top of the torus. The particle motion is also followed outside the last closed magnetic surface. When the boundary (i.e., the surface where the helical currents flow) is sufficiently far from the plasma, the escaping alpha particles are found to remain trapped in the X-point region.