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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
General Kenneth Nichols and the Manhattan Project
Nichols
The Oak Ridger has published the latest in a series of articles about General Kenneth D. Nichols, the Manhattan Project, and the 1954 Atomic Energy Act. The series has been produced by Nichols’ grandniece Barbara Rogers Scollin and Oak Ridge (Tenn.) city historian David Ray Smith. Gen. Nichols (1907–2000) was the district engineer for the Manhattan Engineer District during the Manhattan Project.
As Smith and Scollin explain, Nichols “had supervision of the research and development connected with, and the design, construction, and operation of, all plants required to produce plutonium-239 and uranium-235, including the construction of the towns of Oak Ridge, Tennessee, and Richland, Washington. The responsibility of his position was massive as he oversaw a workforce of both military and civilian personnel of approximately 125,000; his Oak Ridge office became the center of the wartime atomic energy’s activities.”
P.I. Petersen, DIII-D Team
Fusion Science and Technology | Volume 39 | Number 2 | March 2001 | Pages 305-314
Fusion Technology Plenary | doi.org/10.13182/FST01-A11963253
Articles are hosted by Taylor and Francis Online.
An advanced tokamak is characterized by increased confinement, stability and steady state operation. The increased confinement and stability are obtained through modifications to the shape and profiles of the plasma and through stability feedback control. These modifications have to be self-consistent. The increased confinement makes it possible to make smaller and thereby lower cost reactors for the same power output as compared to conventional tokamaks. Four potential modes for advanced tokamaks are currently being studied on DIII-D: radiative improved mode, high internal inductance ℓi mode, negative central shear (NCS) mode, and quiescent double barrier (QDB) mode.
High-density plasma are important for reactors and recent experiments in DIII–D have shown that it is possible to operate substantially above the Greenwald limit. Control of the internal transport barriers that are responsible for the increased confinement have been improved in counter injected neutral beam plasmas. One of the limiting instabilities for the performance of high bootstrap fraction negative central shear plasmas is the resistive wall mode. These modes have to a certain degree been suppressed in DIII–D by using the six-section correction coil. With a newly installed upper inner divertor in DIII–D it has been possible to obtain improved density and impurity control. An upgrade of the electron cyclotron system is being done on DIII–D. Three 1 MW gyrotrons are being added. This system has been used to completely suppress the neoclassical tearing mode by applying electron cyclotron current drive at definite positions and in very localized areas. Finally, the implication of the recent findings for fusion reactors will be discussed.
