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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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Fusion Science and Technology
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Deep Space: The new frontier of radiation controls
In commercial nuclear power, there has always been a deliberate tension between the regulator and the utility owner. The regulator fundamentally exists to protect the worker, and the utility, to make a profit. It is a win-win balance.
From the U.S. nuclear industry has emerged a brilliantly successful occupational nuclear safety record—largely the result of an ALARA (as low as reasonably achievable) process that has driven exposure rates down to what only a decade ago would have been considered unthinkable. In the U.S. nuclear industry, the system has accomplished an excellent, nearly seamless process that succeeds to the benefit of both employee and utility owner.
F. Castejón, J. M. Reynolds, J. M. Fontdecaba, R. Balbín, J. Guasp, D. López-Bruna, I. Campos, L. A. Fernández, D. Fernández-Fraile, V. Martín-Mayor, A. Tarancón
Fusion Science and Technology | Volume 50 | Number 3 | October 2006 | Pages 412-418
Technical Paper | Stellarators | doi.org/10.13182/FST06-A1263
Articles are hosted by Taylor and Francis Online.
It was observed previously that the ion temperature profile of low-density electron cyclotron resonance-heated TJ-II plasmas is almost flat and that energetic ions are present well outside the last closed magnetic surface. The heat diffusivity obtained for such ion temperature profiles is very high, and therefore, transport cannot be described by Fick's law. In this work, ion trajectories with different pitches and starting points have been calculated for the relevant magnetic configuration. It is found that a feasible explanation for such a flat mean energy profile is that ion orbits are wide enough to communicate distant parts of the plasma radius, thus giving an effective flat ion temperature profile, for these low-density (<1019-m-3) plasmas. The distribution function is also obtained without considering collisions; thus, non-Maxwellian features are found. The final particle density shows inhomogeneities on a magnetic surface.
