INTEGRATED RADIATION-MAGNETO-HYDRODYNAMIC SIMULATIONS OF MAGNETIZED BURNING PLASMAS

Considering recent breakthroughs in inertial confinement fusion (ICF), first achieving ignition conditions in NIF shot N210808 and then laser energy breakeven in N221204, modeling efforts have been investigating the effect of imposed magnetic fields on integrated simulations of igniting systems. Previous NIF experiments have shown fusion yield and hotspot temperature to increase in magnetized gas-filled capsules [Moody, PRL 2022] in line with expected scalings [Walsh, POP 2022]. Simulations using the 2D radiation-magneto-hydrodynamics code Lasnex are tuned to approximate data from unmagnetized experiments [Strozzi, POP 2024]. Investigated here is the effect of imposed axial fields up to 100 Tesla on the fusion output of historically best performing ICF shots, specifically N180128, N210808, and N221204. The main effect is increased hotspot temperature due to magnetic insulation, as electron heat flow is constrained perpendicular to the magnetic field and alpha particle trajectories transition to gyro-orbits, enhancing energy deposition into the cold fuel. Magnetic fields must be fastidiously applied however as magnetic pressure can resist the implosion and fields can compromise burn wave propagation [Jones, Nuc. Fus. 1986, Appelbe, POP 2017]. In conclusion it is found that magnetization can increase ion temperature by >50% and neutron yield by >5x. Ongoing work is investigating the effect of magnetization on future, high-energy NIF designs considering up to 3 MJ of laser drive.