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
Robotics & Remote Systems
The Mission of the Robotics and Remote Systems Division is to promote the development and application of immersive simulation, robotics, and remote systems for hazardous environments for the purpose of reducing hazardous exposure to individuals, reducing environmental hazards and reducing the cost of performing work.
Meeting Spotlight
International Conference on Mathematics and Computational Methods Applied to Nuclear Science and Engineering (M&C 2025)
April 27–30, 2025
Denver, CO|The Westin Denver Downtown
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
Apr 2025
Jan 2025
Latest Journal Issues
Nuclear Science and Engineering
May 2025
Nuclear Technology
Fusion Science and Technology
Latest News
TerraPower begins U.K. regulatory approval process
Seattle-based TerraPower signaled its interest this week in building its Natrium small modular reactor in the United Kingdom, the company announced.
TerraPower sent a letter to the U.K.’s Department for Energy Security and Net Zero, formally establishing its intention to enter the U.K. generic design assessment (GDA) process. This is TerraPower’s first step in deployment of its Natrium technology—a 345-MW sodium fast reactor coupled with a molten salt energy storage unit—on the international stage.
Daren P. Stotler, R. J. Goldston, The CIT Team
Fusion Science and Technology | Volume 20 | Number 1 | August 1991 | Pages 7-25
Technical Paper | Plasma Engineering | doi.org/10.13182/FST91-A29639
Articles are hosted by Taylor and Francis Online.
A global reactor performance code employing Monte Carlo techniques has been developed to study the “probability of ignition” and has been applied to several configurations of a compact, high-field ignition tokamak to determine the relative benefits of raising the plasma current and peaking the density profile. Probability distributions for the critical physics parameters in the code are estimated using existing experimental data. An energy confinement scaling representing a 1 to 2.5 times improvement over the L mode is assumed; the range of this multiplier was chosen to reflect the uncertainty in extrapolating the energy confinement time to the high field ignition regime. Even with fairly broad input probability distributions, the probability of ignition improves significantly with increasing plasma current and density profile peaking. Raising the plasma current by 2 MA has about the same impact as raising the peak-to-average density ratio from ∼1 to ∼3. With either this density peaking or a plasma current ≥11 MA, the probability of ignition is computed to be ≥40%. In other cases, values of Q (the ratio of the fusion power to the sum of the ohmic and auxiliary input powers) of the order of 10 are generally obtained. Comparisons of our empirically based confinement assumptions with two theory-based transport models yield conflicting results.