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Remembering ANS member Gil Brown
Brown
The nuclear community is mourning the loss of Gilbert Brown, who passed away on July 11 at the age of 77 following a battle with cancer.
Brown, an American Nuclear Society Fellow and an ANS member for nearly 50 years, joined the faculty at Lowell Technological Institute—now the University of Massachusetts–Lowell—in 1973 and remained there for the rest of his career. He eventually became director of the UMass Lowell nuclear engineering program. After his retirement, he remained an emeritus professor at the university.
Sukesh Aghara, chair of the Nuclear Engineering Department Heads Organization, noted in an email to NEDHO members and others that “Gil was a relentless advocate for nuclear energy and a deeply respected member of our professional community. He was also a kind and generous friend—and one of the reasons I ended up at UMass Lowell. He served the university with great dedication. . . . Within NEDHO, Gil was a steady presence and served for many years as our treasurer. His contributions to nuclear engineering education and to this community will be dearly missed.”
Allen H. Boozer
Fusion Science and Technology | Volume 59 | Number 3 | April 2011 | Pages 561-571
Lecture | Fourth ITER International Summer School (IISS2010) | doi.org/10.13182/FST11-A11697
Articles are hosted by Taylor and Francis Online.
The theory of control of nonaxisymmetric perturbations is dominated by the wide sensitivity range of a tokamak plasma to externally produced magnetic perturbations. External perturbations are characterized by their normal magnetic field [italic B with right arrow above]x[italic n with circumflex accent] on the unperturbed plasma surface. The first spatial distribution of [italic B with right arrow above]x[italic n with circumflex accent] on the unperturbed plasma surface in a sensitivity series is that distribution that at the smallest amplitude has a significant effect on plasma properties. The second distribution of [italic B with right arrow above]x[italic n with circumflex accent] in that series is the distribution to which the plasma has greatest sensitivity while being orthogonal to the first. Two distributions are orthogonal if the integral of their product over the unperturbed plasma surface is zero. Only a limited number of distributions in the sensitivity series can be driven to an unacceptable amplitude by credible construction errors in ITER. Essentially any external coil set that produces a nonaxisymmetric magnetic field of adequate strength with a controllable toroidal phase can null the drive for the distribution of highest plasma sensitivity. However, the simultaneous nulling of not only the first but also of a number of other distributions in the sensitivity series is far more difficult. It is the properties of these distributions of secondary importance that determine both the machine tolerances that are required for successful control and the adequacy of a given set of error field control coils. Nonaxisymmetric fields can also have beneficial effects such as the control of edge-localized modes. Implementation requires driving a normal field distribution to which the beneficial effect is sensitive while not driving detrimental distributions of high plasma sensitivity.
