The quest for laboratory inertial fusion burn in the United States

9th International Conference on Inertial Fusion Sciences and Applications

Crandall, D.H.^1

Independent, United Kingdom^1

关键词: Astrophysical phenomena;    Direct drive implosion;    Hydrodynamic instabilities;    Inertial fusion;    Laser-heated plasmas;    Laser-plasma instabilities;    National ignition facility;    OMEGA Laser Facility;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/717/1/012001/pdf
DOI  :  10.1088/1742-6596/717/1/012001

来源: IOP

【 摘 要 】

Ignition and significant fusion yield from inertial confinement fusion (ICF) remains a grand scientific challenge with significant near-term and long-term applications. The ICF community in the U.S. is executing a coordinated effort to explore three viable approaches: laser x-ray drive, laser direct drive, and magnetic direct drive. Cooperative efforts from multiple institutions are directed at the physics basis of each of the three approaches with advancing diagnostics, precision targets, and improved simulations being the basis for the quest. X-ray drive experiments between 2010 and 2012 at the National Ignition Facility (NIF) gave yields much lower than expected because of both challenging hydrodynamics associated with high capsule convergence (35x) and laser-plasma instabilities (LPI's) in the hohlraum. Recent experiments employing a variation of the laser pulse and resulting in lower convergence and lower hydrodynamic instability growth gave higher yields approaching 1016neutrons (for the first time with significant fusion heating of the fuel), roughly in agreement with predictions for that approach. At the Omega Laser Facility the direct laser drive of the capsule is being developed to determine what could be expected if the NIF were reconfigured for spherical direct drive. Recent experiments on OMEGA, hydrodynamically scaled to the NIF, project to yields similar in nature to those of the best x-ray drive cases. Mitigation of cross-beam energy transfer (CBET) is required for improvement in direct-drive implosions. At the Z pulsed-power facility, a new approach of magnetically pinching a cylinder containing magnetized and laser- heated plasma shows promise for attaining significant fusion yield. Improvements in this technique are being addressed at a number of facilities. In addition to the fusion-yield experiments, a number of basic science studies use the advanced facilities to study plasma physics, materials science, and astrophysical phenomena at extreme parameters not previously available in a laboratory.