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.
Division Spotlight
Human Factors, Instrumentation & Controls
Improving task performance, system reliability, system and personnel safety, efficiency, and effectiveness are the division's main objectives. Its major areas of interest include task design, procedures, training, instrument and control layout and placement, stress control, anthropometrics, psychological input, and motivation.
Meeting Spotlight
Utility Working Conference and Vendor Technology Expo (UWC 2024)
August 4–7, 2024
Marco Island, FL|JW Marriott Marco Island
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 2024
Jan 2024
Latest Journal Issues
Nuclear Science and Engineering
August 2024
Nuclear Technology
Fusion Science and Technology
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 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. 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.”
K. Toi, F. Watanabe, S. Ohdachi, S. Morita, X. Gao, K. Narihara, S. Sakakibara, K. Tanaka, T. Tokuzawa, H. Urano, A. Weller, I. Yamada, L. Yan, LHD Experiment Group
Fusion Science and Technology | Volume 58 | Number 1 | July-August 2010 | Pages 61-69
Chapter 3. Confinement and Transport | Special Issue on Large Helical Device (LHD) | doi.org/10.13182/FST10-A10794
Articles are hosted by Taylor and Francis Online.
The L-H transition was observed in a unique helical divertor configuration where the core plasma is surrounded by ergodic layer, exhibiting rapid increase in edge electron density with sudden depression of H emission. Just after the transition, edge transport barrier (ETB) is formed at the plasma edge in the magnetic hill region, developing a steep density gradient. ETB region extends in ergodic layer beyond the last closed flux surface defined by the vacuum field. The transition occurs in relatively high beta plasmas when neutral beam absorbed power (Pabs) exceeds one to three times the ITER H-mode power threshold. Improvement of energy confinement time is modest (<1.1) for the ISS95 international stellarator scaling, whereas the particle confinement is clearly improved. The ETB width tends to increase with the increase in the toroidal beta at the ETB shoulder. ETB formation leads to destabilization of edge magnetohydrodynamic (MHD) modes with m/n = 2/3 or 1/2 (m and n being the poloidal and toroidal mode numbers) in ETB region of the inward-shifted configurations. Edge-localized modes (ELMs) are excited by these edge MHD modes through nonlinear evolution. Sometimes in outward-shifted plasmas, edge MHD modes are clearly suppressed in the H-phase and lead to an ELM-free H-mode. When large m/n = 1/1 resonant magnetic perturbations are applied to neutral beam injection-heated plasmas, the transition takes place at lower line-averaged electron density having the modest increase in electron temperature and small-amplitude ELMs.