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The Radiation Protection and Shielding Division is developing and promoting radiation protection and shielding aspects of nuclear science and technology — including interaction of nuclear radiation with materials and biological systems, instruments and techniques for the measurement of nuclear radiation fields, and radiation shield design and evaluation.
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Utility Working Conference and Vendor Technology Expo (UWC 2024)
August 4–7, 2024
Marco Island, FL|JW Marriott Marco Island
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Latest News
Vogtle-3 shuts down for valve issue
One of the new Vogtle units in Georgia was shut down unexpectedly on Monday last week for a valve issue that has since been investigated and repaired. According to multiple local news outlets, Georgia Power reported on July 17 that Unit 3 was back in service.
Southern Company spokesperson Jacob Hawkins confirmed that Vogtle-3 went off line at 9:25 p.m. local time on July 8 “due to lowering water levels in the steam generators caused by a valve issue on one of the three main feedwater pumps.”
Donald A. Spong, Jeff A. Holmes, Jean-n. Leboeuf, Peggy Jo Christenson
Fusion Science and Technology | Volume 18 | Number 3 | November 1990 | Pages 496-504
Alpha Particles in Fusion Research | Technical Paper | doi.org/10.13182/FST90-A29285
Articles are hosted by Taylor and Francis Online.
Alpha-particle populations can significantly alter existing magnetohydrodynamic (MHD) instabilities in tokamaks through kinetic effects and coupling to otherwise stable shear Alfvén waves. Resonances of the trapped alpha-particle precessional drift, with the usual ballooning mode diamagnetic frequency (ω*i/2) and the toroidicity-induced Alfvén eigenmode (TAE), are considered. These are examined for noncircular tokamaks in the high-n ballooning limit using an isotropic alpha-particle slowing down distribution and retaining the full-energy and pitch-angle dispersion in the alpha-particle drift frequency. Applying this to the Compact Ignition Tokamak (CIT) and the International Thermonuclear Experimental Reactor (ITER) indicates that ballooning instabilities can persist at betas below the ideal MHD threshold. These are especially dominated by the destabilization of the TAE mode. In addition, a hybrid fluid-particle approach for simulating alpha-particle effects on pressure-gradient driven instabilities is described.