A. Improving the basis for future burning plasma experiments through research on magnetic confinement configuration optimization.:
A1. Reduce operational and maintenance complexity. The ITER-like concept requires a doubly connected toroidal first wall and blanket incorporating three coil sets. For an optimized reactor the cost could be greatly decreased if it were simply connected and/or had less coil sets.
A2. Higher beta. Beta is the ratio of plasma pressure to magnetic pressure. The reactor cost will be decreased considerably if beta could be increased to above 10%.
A3. Better sustainment of magnetic and density profiles. High efficiency current drive methods, would remove the restriction that profiles must have high bootstrap fraction in the ITER-like reactor. Current drive and profile control at high power efficiencies would be an enabling technology for many attractive innovative confinement concepts and better profile control of low-aspect-ratio symmetric tori is needed. Methods of sustaining the deuterium, tritium, helium, and impurity density profiles, which is essential for controlling high-Q burning plasma, need improvement.
A4. Control of plasma disruption. Disruptions must be understood and controlled before a concept can be considered viable. They are not yet controllable for the mainline concept and ideas are needed for achieving this understanding and control.
A5. Better utilization of 3D magnetic fields. Improving toroidal confinement performance through quasi-symmetric and three-dimensional magnetic field shaping is an important area of research. Divertor designs for three-dimensional magnetic confinement configurations are needed.
A6. Improved plasma chamber/first wall. Chamber lifetime is a major cost issue with fusion where 14MeV neutrons and plasma exhaust power must be absorbed without damaging internal components or activating the first wall. Ideas that lead to systems that have better first wall, divertor and chamber solutions are needed.
A7. Better computational simulations. Progress with fusion will be more rapid with the development of an experimentally-validated predictive capability for magnetically-confined fusion plasmas.
A8. Other improvements for magnetic confinement.
B. Improving the basis for future burning plasma experiments through research on inertial fusion
B1. Better targets and drivers. Higher gain, lower required energy, asymmetric (non-4pi) illumination and lower cost targets would improve the economics of IFE reactors. More efficient, lower cost, and high repetition rate drivers are needed.
B2. Improved plasma chamber. Transmitting the power from the source through the chamber wall and onto the target at a high repetition rate with a low-cost and low maintenance-cost system is required. As in magnetic fusion, chamber lifetime is a major cost issue where 14MeV neutrons must be absorbed without overly damaging or activating the chamber/first wall. Concepts that lead to systems that have easier first wall and chamber solutions are needed.
B3. Computational simulations. Progress with inertial fusion will be more rapid with the development of an experimentally-validated predictive capability.
B4. Other improvements for inertial confinement.
C. Other fusion methods and ideas
D. Enhanced fundamental understanding of magnetic confinement
D1. How does magnetic field structure impact plasma confinement?
D2. What is the maximum beta that can be achieved in laboratory plasma?
D3. How can external control and plasma self-organization be used to improve performance?
D4. How does turbulence cause heat, particle, and momentum to escape from plasma?
D5. How are electromagnetic fields and mass flows generated in plasmas?
D6. How do magnetic fields in plasmas reconnect and dissipate energy?
D7. Other than the above.
E. Enhanced fundamental understanding of inertial confinement
E1. How do hydrodynamic instabilities affect implosions to high energy density?
E2. How do electromagnetic waves interact with plasma?
E3. How do high-energy particles interact with plasma?
E4. Other than the above.