Journal Article

Demonstration of a hydrodynamically equivalent burning plasma in direct-drive inertial confinement fusion

Gatu-Johnson, M., Fella, C., Knauer, J. P., Campbell, E. M., Ivancic, S., Marozas, J. A., Forrest, C. J., Woo, K. M., Scullin, W., Morse, S. F. B., Ejaz, R., Janezic, R. T., Farrell, M., Regan, S. P., Deeney, C., Petrasso, R. D., Turnbull, D., Rosenberg, M. J., Guzman, D., Churnetski, K., Betti, R., Patel, D., Murray, J., Igumenshchev, I. V., Edgell, D. H., Shuldberg, C., Goncharov, V. N., Bauer, K. A., Labuzeta, M., Frenje, J. A., Williams, C. A., Radha, P. B., Farmakis, P., Theobald, W., Thomas, C. A., Heuer, P. V., Shah, R. C., Koch, M., Stoeckl, C., Bonino, M. J., Bredesen, D., Gopalaswamy, V., Epstein, R., Harding, D. R., Sampat, S., Hu, S. X., McClow, H., Collins, T. J. B., Carroll-Nellenbeck, J., Solodov, A. A., Glebov, V. Yu, Serrato, B., Cao, D., Waxer, L. J., Lees, A., Anderson, K. S.

2024

Overview

Focussing laser light onto the surface of a small target filled with deuterium and tritium implodes it and leads to the creation of a hot and dense plasma, in which thermonuclear fusion reactions occur. In order for the plasma to become self-sustaining, the heating of the plasma must be dominated by the energy provided by the fusion reactions—a condition known as a burning plasma. A metric for this is the generalized Lawson parameter, where values above around 0.8 imply a burning plasma. Here, we report on hydro-equivalent scaling of experimental results on the OMEGA laser system and show that these have achieved core conditions that reach a burning plasma when the central part of the plasma, the hotspot, is scaled in size by at least a factor of 3.9 ± 0.10, which would require a driver laser energy of at least 1.7 ± 0.13 MJ. In addition, we hydro-equivalently scale the results to the 2.15 MJ of laser energy available at the National Ignition Facility and find that these implosions reach 86% of the Lawson parameter required for ignition. Our results support direct-drive inertial confinement fusion as a credible approach for achieving thermonuclear ignition and net energy in laser fusion. Hydro-equivalent scaling of recent direct-drive inertial confinement fusion implosions shows that a burning plasma can be achieved with a higher laser energy.

• Publisher: Nature Publishing Group UK,Nature Publishing Group,Nature Publishing Group (NPG)
• Subject: 639/4077/4091/4093 / 639/766/1960/1135 / 70 PLASMA PHYSICS AND FUSION TECHNOLOGY / Atomic / Classical and Continuum Physics / Complex Systems / Condensed Matter Physics / Dense plasmas / Deuterium / Energy / Equivalence / Ignition / Implosions / Inertial confinement fusion / Laser fusion / Laser-produced plasmas / Lasers / Mathematical and Computational Physics / Molecular / Nuclear fusion and fission / Optical and Plasma Physics / Parameters / Physics / Physics and Astronomy / Plasma / Theoretical / Thermonuclear fusion / Tritium