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.
V. Sokolov, X. Wei, A. K. Sen
Fusion Science and Technology | Volume 59 | Number 1 | January 2011 | Pages 154-157
doi.org/10.13182/FST11-A11596
Articles are hosted by Taylor and Francis Online.
The anomalous radial transport generated by drift wave turbulence is a fundamental open physics question in magnetic confinement systems, both in modern tokamaks and current and next generation mirror machines. The role of self-generated zonal flows (ZF) in transport regulation via its shear is a potent concept and a physics issue. ZF are believed to be spontaneously excited by drift wave turbulence via Reynolds stress from small-scale fluctuations to large-scale flow.A basic physics experimental study of zonal flows associated with ITG (ion temperature gradient) drift modes has been performed in the Columbia Linear Machine (CLM). The difficult problem of detection of ZF has been solved via a novel diagnostic using the paradigm of FM (frequency modulation) in radio transmission. We find a power spectrum peak at ITG (`carrier') frequency of ~120 kHz and FM sidebands at frequency of ~2 kHz. We have definitively identified ZF with azimuthal and axial symmetry (k = 0, k// [approximately equal] 0) and radially inhomogeneous (kr [not equal] 0) flow structures in cylindrical plasmas in uniform axisymmetric magnetic field. However, quantitatively, the stabilizing effect of ZF shear appears to be small and no significant isotopic effects are observed. The unique complementary roles of ion acoustic damping and ZF shearing in the saturation of ITG have been experimentally demonstrated using stabilizing and destabilizing feedback techniques. Theoretically ZF is supposed to be saturated via ii. As this is very small both in tokamaks and CLM, we investigate the scaling ZF with in in which can be significant in CLM.
