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The mission of the Decommissioning and Environmental Sciences (DES) Division is to promote the development and use of those skills and technologies associated with the use of nuclear energy and the optimal management and stewardship of the environment, sustainable development, decommissioning, remediation, reutilization, and long-term surveillance and maintenance of nuclear-related installations, and sites. The target audience for this effort is the membership of the Division, the Society, and the public at large.
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Conference on Nuclear Training and Education: A Biennial International Forum (CONTE 2025)
February 3–6, 2025
Amelia Island, FL|Omni Amelia Island Resort
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Fusion Science and Technology
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A more open future for nuclear research
A growing number of institutional, national, and funder mandates are requiring researchers to make their published work immediately publicly accessible, through either open repositories or open access (OA) publications. In addition, both private and public funders are developing policies, such as those from the Office of Science and Technology Policy and the European Commission, that ask researchers to make publicly available at the time of publication as much of their underlying data and other materials as possible. These, combined with movement in the scientific community toward embracing open science principles (seen, for example, in the dramatic rise of preprint servers like arXiv), demonstrate a need for a different kind of publishing outlet.
C. L. Fiore, D. R. Ernst, J. E. Rice, K. Zhurovich, N. Basse, P. T. Bonoli, M. J. Greenwald, E. S. Marmar, S. J. Wukitch
Fusion Science and Technology | Volume 51 | Number 3 | April 2007 | Pages 303-316
Technical Paper | Alcator C-Mod Tokamak | doi.org/10.13182/FST07-A1424
Articles are hosted by Taylor and Francis Online.
Internal transport barriers (ITBs) marked by steep density and pressure profiles and reduction of core transport are obtained in Alcator C-Mod. Transient single barriers are observed at the back-transition from H- to L-mode and also when pellet injection is accompanied by ion cyclotron resonance frequency (ICRF) power. Double barriers are induced with injection of off-axis ICRF power deposition. These also arise spontaneously in ohmic H-mode plasmas when the H-mode lasts for several energy confinement times. C-Mod provides a unique platform for studying such discharges: The ions and electrons are tightly coupled by collisions with Ti/Te = 1, and the plasma has no internal particle or momentum sources. ITB plasmas with average pressure greater than 1 atm have been obtained. To form an ITB, particle and thermal flux are reduced in the barrier region, allowing the neoclassical pinch to peak the density while maintaining the central temperature. Gyrokinetic simulation suggests that long-wavelength drift wave turbulence in the core is marginally stable at the ITB onset, but steepening of the density profile destabilizes trapped electron modes (TEMs) inside the barrier. The TEM ultimately drives sufficient outgoing particle flux to balance the inward pinch and halt further density rise, which allows control of particle and impurity peaking.
