We examine the potential that imposed magnetic fields of tens of Tesla that increase to greater than 10 kT (100 MGauss) under implosion compression may relax the conditions required for ignition and propagating burn in indirect-drive inertial confinement fusion (ICF) targets. This may allow the attainment of ignition, or at least significant fusion energy yields, in presently performing ICF targets on the National Ignition Facility (NIF) that today are sub-marginal for thermonuclear burn through adverse hydrodynamic conditions at stagnation [Doeppner et al., Phys. Rev. Lett. 115, 055001 (2015)]. Results of detailed two-dimensional radiation-hydrodynamic-burn simulations applied to NIF capsule implosions with low-mode shape perturbations and residual kinetic energy loss indicate that such compressed fields may increase the probability for ignition through range reduction of fusion alpha particles, suppression of electron heat conduction, and potential stabilization of higher-mode Rayleigh-Taylor instabilities. Optimum initial applied fields are found to be around 50 T. Given that the full plasma structure at capsule stagnation may be governed by three-dimensional resistive magneto-hydrodynamics, the formation of closed magnetic field lines might further augment ignition prospects. Experiments are now required to further assess the potential of applied magnetic fields to ICF ignition and burn on NIF.

A simulation model for current drive by lower hybrid slow waves has been generalized to accommodate elongated plasma cross-sections. Toroidal ray trajectories are computed from the magnetic field, density and temperature distributions obtained from a numerical, free boundary solution of the Grad-Shafranov equation. A numerical solution of a relativistic Fokker-Planck equation is used to compute the absorbed power and the driven current. This lower hybrid model has been incorporated into the ACCOME code which iterates between solutions of the Grad-Shafranov equation and computation of the driven current until a self-consistent solution is obtained. Current driven by neutral beams, neoclassical effects and an Ohmic electric field in addition to lower hybrid waves is included. The model is applied to the proposed ITER design under steady state, non-inductive operation

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A local, two-dimensional (in velocity space), time-dependent, quasi-linear Ion Cyclotron Range of Frequencies (ICRF) Fokker-Planck model is used to study heating in PLT and NUWMAK reactor plasmas. It is found that PLT ICRF experimental results, including tail formation, are well modelled when charge-exchange, radial and radiation losses and Ohmic heating are incorporated. For the NUWMAK reactor parameters, the lower-radiofrequency power per resonant particle and high density provide an isotropic Maxwellian plasma describable by fluid models.

It is shown that radial profiles of the safety factor q(r), necessary to access the socalled "second stability" regime in shaped, low aspect ratio tokamnaks, can be achieved via off-axis lower hybrid current drive (LHCD). In order to accurately model the required current profiles, our previous simulation code for LHCD has been extended to noncircular equilibria and combined with an MHD equilibrium solver. As a particular example, results will be presented for Versator Upgrade tokamak parameters.