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Radiation Protection & Shielding
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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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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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Nuclear News 40 Under 40 discuss the future of nuclear
Seven members of the inaugural Nuclear News 40 Under 40 came together on March 4 to discuss the current state of nuclear energy and what the future might hold for science, industry, and the public in terms of nuclear development.
To hear more insights from this talented group of young professionals, watch the “40 Under 40 Roundtable: Perspectives from Nuclear’s Rising Stars” on the ANS website.
J. T. Hogan, D. L. Hillis, J.D. Galambos, N. A. Uckan, K. H. Dippel, K. H. Finken, R. A. Hulse, R. V. Budny
Fusion Science and Technology | Volume 19 | Number 3 | May 1991 | Pages 1509-1512
ITER | Proceedings of the Ninth Topical Meeting on the Technology of Fusion Energy (Oak Brook, Illinois, October 7-11, 1990) | doi.org/10.13182/FST91-A29555
Articles are hosted by Taylor and Francis Online.
Many studies have shown the importance of the ratio τHe/τE in determining the level of He ash accumulation in future reactor systems. Results of the first tokamak He removal experiments have been analyzed, and a first estimate of the ratio τHe/τE to be expected for future reactor systems has been made. The experiments were carried out for neutral-beam-heated plasmas in the TEXTOR tokamak at KFA Jülich. Helium was injected both as a short puff and continuously and subsequently extracted with the Advanced Limiter Test-II (ALT-II) pump limiter. The rate at which the He density decays has been determined with absolutely calibrated charge-exchange spectroscopy and compared with theoretical models, using the Multiple Impurity Species Transport (MIST) code. An analysis of energy confinement has been made with the Princeton Plasma Physics Laboratory (PPPL) TRANSP code, to distinguish beam from thermal confinement, especially for low-density cases. The ALT-II pump limiter system is found to exhaust the He with a maximum exhaust efficiency (eight pumps) of ∼8%. We find 1< τHe/τE < 3.3 for the database of cases analyzed to date. Analysis with the International Thermonuclear Experimental Reactor (ITER) TETRA systems code shows that these values would be adequate to achieve the required He concentration with the present ITER divertor He extraction system.