Thinking about the Future

Brian Gilbert, associate professor of chemistry, has been influential in the education of Kevin Romero, class of 2015

Optimisation of out-vessel magnetic diagnostics for plasma boundary reconstruction in tokamaks

To improve the low frequency spectrum of magnetic field measurements of future tokamak reactors such as ITER, several steady state magnetic sensor technologies have been considered. For all the studied technologies it is always advantageous to place the sensors outside the vacuum vessel and as far away from the reactor core to minimize radiation damage and temperature effects, but not so far as to compromise the accuracy of the equilibrium reconstruction. We have studied to what extent increasing the distance between out-vessel sensors and plasma can be compensated for sensor accuracy and/or density before the limit imposed by the degeneracy of the problem is reached. The study is particularized for the Swiss TCV tokamak, due to the quality of its magnetic data and its ability to operate with a wide range of plasma shapes and divertor configurations. We have scanned the plasma boundary reconstruction error as function of out-vessel sensor density, accuracy and distance to the plasma. The study is performed for both the transient and steady state phases of the tokamak discharge. We find that, in general, there is a broad region in the parameter space where sensor accuracy, density and proximity to the plasma can be traded for one another to obtain a desired level of accuracy in the reconstructed boundary, up to some limit. Extrapolation of the results to a tokamak reactor suggests that a hybrid configuration with sensors inside and outside the vacuum vessel could be used to obtain a good boundary reconstruction during both the transient and the flat-top of the discharges, if out-vessel magnetic sensors of sufficient density and accuracy can be placed sufficiently far outside the vessel to minimize radiation damage.Comment: 36 pages, 17 figures, Accepted for publication in Nuclear Fusio

NASA OAST and its role in space technology development

Several new programs, efforts in space research and technology, are introduced that the Office of Aeronautics and Space Technology has begun to support. The four key issues that currently are consuming NASA's energies and should be of great concern are listed. NASA is placing its emphasis in space on: (1) reconstituting the Shuttle capability; (2) maintaining the space station momentum; (3) resolving the current science mission backlog; and (4) rebuilding the technology base. Ways of implementing and funding these issues are discussed

Coping With Discrimination Among Mexican Descent Adolescents

The current research is designed to explore the relationship among discrimination stress, coping strategies, and self-esteem among Mexican descent youth (N = 73, age 11-15 years). Results suggest that primary control engagement and disengagement coping strategies are positively associated with discrimination stress. Furthermore, self-esteem is predicted by an interaction of primary control engagement coping and discrimination stress, such that at higher levels of discrimination stress, youth who engaged in more primary control engagement coping reported higher self-esteem. The authors’ findings indicate that Mexican descent youth are actively finding ways to cope with the common experience of negative stereotypes and prejudice, such that their self-esteem is protected from the stressful impact of discrimination and prejudice. Implications of these findings for Latino/a youth resilience are discussed