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Materials Science & Technology
The objectives of MSTD are: promote the advancement of materials science in Nuclear Science Technology; support the multidisciplines which constitute it; encourage research by providing a forum for the presentation, exchange, and documentation of relevant information; promote the interaction and communication among its members; and recognize and reward its members for significant contributions to the field of materials science in nuclear technology.
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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
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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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Latest News
Judge temporarily blocks DOE’s move to slash university research funding
A group of universities led by the American Association of Universities (AAU) acted swiftly to oppose a policy action by the Department of Energy that would cut the funds it pays to universities for the indirect costs of research under DOE grants. The group filed suit Monday, April 14, challenging a what it termed a “flagrantly unlawful action” that could “devastate scientific research at America’s universities.”
By Wednesday, the U.S. District Court judge hearing the case issued a temporary restraining order effective nationwide, preventing the DOE from implementing the policy or terminating any existing grants.
Thomas Elevant, Hans E. Brelén, Per G. Lindén, Jan Scheffel
Fusion Science and Technology | Volume 32 | Number 2 | September 1997 | Pages 304-318
Technical Paper | Experimental Device | doi.org/10.13182/FST97-A19900
Articles are hosted by Taylor and Francis Online.
In the next generation of magnetic fusion experiments, such as the International Thermonuclear Experimental Reactor (ITER), information on ion temperature profiles will be needed for burn optimization and transport studies. The feasibility of obtaining these profiles for the core plasma (r < 0.75 of minor radius) directly from the width of measured 14-MeV neutron energy spectra is demonstrated for Maxwellian ion distributions. Neutron energy spectra are calculated using the Monte Carlo technique. Reaction kinematics and velocity distribution of the reacting ions are taken into account, which enables the resulting neutron flux and energy distribution entering a defined collimator to be calculated. Energy spectra of neutrons emitted along a line of sight (LOS) are obtained by adding the contributions from a large number of subvolumes. The associated correction factor (peak temperature over LOS measured temperature) depends on the ion temperature and on the shapes of the temperature and density profiles. The resulting accuracy in the evaluated ion temperature profiles is expected to be better than ± 10%. However, this can be improved to ±5% provided that the ion density profile shape is known. The relative accuracy is estimated to be better than ±5%. Features of several spectrometer candidates are briefly described in relation to ITER conditions and measurement requirements. A time-of-flight (TOF) neutron spectrometer is outlined. Experiments with a test device confirm the calculated energy resolution and separation of neutron from gamma events. The spectrometer is shown to be applicable to ITER under both ohmically heated and ignited conditions. A feedback system will be used to control the detector count rate at high neutron flux levels to accommodate the large dynamic neutron flux range from 5 × 106 to 5 × 1010 n/(cm2 · s). An array of five to nine TOF spectrometers provides ion temperature profiles that satisfy ITER measurement requirements, i.e., Ti ≥ 2.5 keV; 10% accuracy; and spatial and temporal resolutions of 30 cm and 100 ms, respectively.
