To reach the pressures and densities required for ignition, it may be necessary to develop an approach to design that makes it easier for simulations to guide experiments. Here, we report on a new ...short-pulse inertial confinement fusion platform that is specifically designed to be more predictable. Furthermore, the platform has demonstrated 99%+0.5% laser coupling into the hohlraum, high implosion velocity (411 km/s), high hotspot pressure (220+60 Gbar), and high cold fuel areal density compression ratio (>400), while maintaining controlled implosion symmetry, providing a promising new physics platform to study ignition physics.
We have used x-ray diffraction with subnanosecond temporal resolution to measure the lattice parameters of orthogonal planes in shock compressed single crystals of silicon (Si) and copper (Cu). ...Despite uniaxial compression along the (400) direction of Si reducing the lattice spacing by nearly 11%, no observable changes occur in planes with normals orthogonal to the shock propagation direction. In contrast, shocked Cu shows prompt hydrostaticlike compression. These results are consistent with simple estimates of plastic strain rates based on dislocation velocity data.
Recent experiments systematically studied subscale beryllium-capsule implosions on NIF A.B. Zylstra et al., Phys. Plasmas 26, 052707 (2019), finding that the performance was well explained by ...invoking an inline model for mix at the fuel ablator interface. This model is optimistic about the performance of full-scale beryllium implosions, motivating an exploratory study on tactics for fielding larger capsules within the current limits of power and energy available at NIF. Here we report the results of that work, finding that using a ‘picketless’ pulse would allow a 25% increase in capsule size, which is predicted to substantially improve performance.
In this talk, we will discuss the progress towards ignition on the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory (LLNL) in Northern California. We will cover the some of ...the setbacks encountered during the progress of the research at NIF, but also cover the great advances that have been made including the achievements of greater than unity fusion `fuel gain' and alpha-heating dominated fusion plasmas. The research strategy for the future will also be discussed.
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