DIII-D physics research addresses critical challenges for the operation of ITER and the next generation of fusion energy devices. This is done through a focus on innovations to provide solutions for high performance long pulse operation, coupled with fundamental plasma physics understanding and model validation, to drive scenario development by integrating high performance core and boundary plasmas. Substantial increases in off-axis current drive efficiency from an innovative top launch system for EC power, and in pressure broadening for Alfven eigenmode control from a co-/counter-I p steerable off-axis neutral beam, all improve the prospects for optimization of future long pulse/steady state high performance tokamak operation. Fundamental studies into the modes that drive the evolution of the pedestal pressure profile and electron vs ion heat flux validate predictive models of pedestal recovery after ELMs. Understanding the physics mechanisms of ELM control and density pumpout by 3D magnetic perturbation fields leads to confident predictions for ITER and future devices. Validated modeling of high-Z shattered pellet injection for disruption mitigation, runaway electron dissipation, and techniques for disruption prediction and avoidance including machine learning, give confidence in handling disruptivity for future devices. For the non-nuclear phase of ITER, two actuators are identified to lower the L–H threshold power in hydrogen plasmas. With this physics understanding and suite of capabilities, a high poloidal beta optimized-core scenario with an internal transport barrier that projects nearly to Q = 10 in ITER at ∼8 MA was coupled to a detached divertor, and a near super H-mode optimized-pedestal scenario with co-I p beam injection was coupled to a radiative divertor. The hybrid core scenario was achieved directly, without the need for anomalous current diffusion, using off-axis current drive actuators. Also, a controller to assess proximity to stability limits and regulate β N in the ITER baseline scenario, based on plasma response to probing 3D fields, was demonstrated. Finally, innovative tokamak operation using a negative triangularity shape showed many attractive features for future pilot plant operation.

In the late 1960s and early 1970s, the articulation of politics and sound became explicitly marked during the civil rights transition to embryonic types of racial nationalism, black power and the novel forms of ‘citizenship’ implied therein. Music mediated and registered these critical shifts in political outlook, structural change and black collectivity. Yet, despite the power of black soundings to communicate or gesture toward a particular political sensibility, black popular music in particular remained elusive to those political workers most invested in identifying the articulations of popular sound aesthetics and the masses. Popular music, and soul culture more generally, frustrated nationalist efforts at enlisting the black masses, a failure that paradoxically reflected black nationalism’s inability to appeal to and enlist the political potential of the mass black public that it so valorised. %This article explores the political-aesthetic interface particularly as it played out in the relationship between cultural nationalism and black popular music. This relationship offers a powerful index of the correspondence and dissonance between the political intentions of nationalist political workers and the political desires of the urban masses. It is argued that both the formal attempts at producing revolutionary cultural products and the broader influence and reception that black nationalist politics had within the field of black popular culture were in significant ways less communicative of collective political will and desire than emergent popular musical formations.

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We present the design of ATJ graphite [1] rods developed for ablation experiments under high heat flux (up to 50 MW/m2) in the lower divertor of the DIII-D tokamak [2], a magnetic plasma confinement device. This work is motivated by the need to test ablation models relevant to carbon-based thermal shields used in high-speed spacecraft atmospheric entries, where the heat fluxes encountered can be comparable to those achieved in the DIII-D divertor plasma. Several different designs for the flow-facing side of the rod are analyzed, including “sharp nose,” “blunt,” and “concave”. The last shape is studied for its potential to lower heat fluxes at the rod surface by increased radiation from trapped neutrals and reduced parallel plasma pressure. We also analyze the possibility of applying a thin (approximately 30 microns) layer of silicon carbide (SiC) to the exposed part of several carbon ablation rods to benchmark its erosion calculations and lifetime predictions. Such calculations are of interest as SiC represents a promising material for both thermal protection systems (TPS) and a fusion plasma-facing material (PFM). [3,4] Preliminary results from the DIII-D rod ablation experiments are also discussed.