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Education, Training & Workforce Development
The Education, Training & Workforce Development Division provides communication among the academic, industrial, and governmental communities through the exchange of views and information on matters related to education, training and workforce development in nuclear and radiological science, engineering, and technology. Industry leaders, education and training professionals, and interested students work together through Society-sponsored meetings and publications, to enrich their professional development, to educate the general public, and to advance nuclear and radiological science and engineering.
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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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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.
Henry Chiu
Fusion Science and Technology | Volume 34 | Number 3 | November 1998 | Pages 564-567
Plasma Engineering (Poster Session) | doi.org/10.13182/FST98-A11963673
Articles are hosted by Taylor and Francis Online.
The neutral beam systems of DIII-D, a National Fusion Facility at General Atomics, are used both for heating the plasma, and as tools for plasma diagnostics. The spatial distribution (profile) and energy of the beam is used in the absolute calibration of both the Charge Exchange Recombination (CER) and Motional Stark Effect (MSE) diagnostics. The CER diagnostic is used to make spatially and temporally resolved measurements of ion temperature and poloidal and toroidal rotational velocities. These measurements are made by visible spectroscopy of the Doppler shifted He II (468.6 nm), C VI (529.1 nm) and B V(494.5 nm) spectral lines, excited by the charge exchange recombination events between the plasma ions and the beam neutrals. As such, the spatial distribution of the beam is needed for an absolute calibration of the CER diagnostic. The MSE diagnostic measures the internal poloidal field profile in the plasma. MSE measures the polarization angle of the Stark broadned neutral beam Dα emission due to the Vbeam × B motional electric field. Again, the spatial profile of the neutral beam is needed for the absolute calibration of the MSE diagnostic.
In the past, the beam spatial profile used in these calibrations was derived from beam divergence calculations and IR camera observations on the tokamak inboard target tiles. Two experimental methods are now available to better determine the beam profile. In one method, the Doppler shifted Dα light from the energetic neutrals are measured, and the full-width at half-maximum (FWHM) of the beam can be inferred from the measured divergence of the Dα light intensity. The other method for determining the beam profile uses the temperature gradients measured by the thermocouples mounted on the calorimeter. A new iterative fitting routine for the measured thermocouple data has been developed to fit theoretical models on the dispersion of the beam. The results of both methods are compared, and used to provide a new experimental verification of the beam profile.
