Symmetric inertial-confinement-fusion-capsule implosions in a double-z-pinch-driven hohlraum

Area of Science:

• Plasma Physics
• Fusion Energy
• High-Energy-Density Physics

Background:

• Inertial confinement fusion (ICF) is a leading approach to achieving fusion energy.
• Pulsed-power-driven ICF offers a distinct pathway for fusion energy research.
• Previous ICF experiments have faced challenges in achieving sufficient capsule drive and symmetry.

Purpose of the Study:

• To perform initial capsule implosions for a novel ICF concept driven by Z pinches.
• To assess the capsule drive and radiation symmetry in a pulsed-power ICF configuration.
• To evaluate the convergence ratio achieved in these experiments.

Main Methods:

• Utilizing two Z pinches to drive a cylindrical hohlraum.
• Conducting capsule implosions at a specific physical scale with a 20-MA current.
• Measuring capsule shell shape to determine radiation symmetry.
• Calculating the convergence ratio of the imploded capsule.

Main Results:

• Achieved a capsule drive of 70+/-5 eV, a significant step for the proposed ICF concept.
• Measured polar radiation symmetry within a factor of 1.6-4 of ignition requirements.
• Obtained the highest convergence ratio (14-21) to date in any pulsed-power ICF system.

Conclusions:

• The initial experiments validate the feasibility of the proposed Z-pinch-driven ICF concept.
• The achieved symmetry and convergence ratio represent critical progress toward ignition.
• Further research with higher currents (e.g., 60-MA) is warranted to reach the target 220 eV drive.