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Division Spotlight
Young Members Group
The Young Members Group works to encourage and enable all young professional members to be actively involved in the efforts and endeavors of the Society at all levels (Professional Divisions, ANS Governance, Local Sections, etc.) as they transition from the role of a student to the role of a professional. It sponsors non-technical workshops and meetings that provide professional development and networking opportunities for young professionals, collaborates with other Divisions and Groups in developing technical and non-technical content for topical and national meetings, encourages its members to participate in the activities of the Groups and Divisions that are closely related to their professional interests as well as in their local sections, introduces young members to the rules and governance structure of the Society, and nominates young professionals for awards and leadership opportunities available to members.
Meeting Spotlight
ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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!
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Latest News
Norway’s Halden reactor takes first step toward decommissioning
The government of Norway has granted the transfer of the Halden research reactor from the Institute for Energy Technology (IFE) to the state agency Norwegian Nuclear Decommissioning (NND). The 25-MWt Halden boiling water reactor operated from 1958 to 2018 and was used in the research of nuclear fuel, reactor internals, plant procedures and monitoring, and human factors.
J. D. Galambos, Y.-K. Martin Peng
Fusion Science and Technology | Volume 19 | Number 1 | January 1991 | Pages 31-42
Technical Paper | Fusion Fuel Cycle | doi.org/10.13182/FST91-A29313
Articles are hosted by Taylor and Francis Online.
The D-3He ignition and burn criteria for tokamaks and spherical torus reactors are examined in a global analysis with profile corrections. Particle confinement and ash buildup effects are included with the power balance, which results in an increased sensitivity of the ignition criteria to losses via bremsstrahlung and synchrotron radiation. Plasma beta scaling via an ɛβp limit provides the needed aspect ratio (A) dependence and permits an analysis in all A values of the first and second stability regimes. Energy confinement time (τE) associated with particle diffusion (τp) and energy conduction (τc) is used. The ignition condition for minimum nτE is found to be sensitive to beta but not to the magnetic field. Steady-state burn in second stability tokamaks (ξβp ≥ 0.6) at high A (>4) with average synchrotron wall reflectivities below 95% requires nτE above 5 × 1021 m−3 · s or strong plasma elongation (κ > 3). Ignition in a spherical torus can be achieved with wall reflectivities below 80% and at nτE ≤ 1021 m−3 · s, without requiring strong plasma shaping or ɛβp > 0.6. The need to minimize nτE for ignition and burn strongly limits the synchrotron radiation loss to <20% of the fusion power for all values of A. Synchrotron power fractions can be increased, but only to 40%, due to an upper bound on nτE. Further increases of this fraction can be obtained only by assuming preferential ash removal.