Mission: Fusion energy (among others)
Back in August (just after my last periodic check-in on their progress) they posted this: https://www.llnl.gov/news/newsreleases/ ... 08-04.html
http://www.bbc.co.uk/news/science-environment-24429621"The yield was significantly greater than the energy deposited in the hot spot by the implosion," said Ed Moses, principle associate director for NIF and Photon Science. "This represents an important advance in establishing a self-sustaining burning target, the next critical step on the path to fusion ignition on NIF."
The experiment was designed to resist breakup of the high velocity imploding ablator (shell of the target capsule) that has degraded the performance of previous experiments by lowering compression of the target. To create this resistance, the laser power is turned up during the picket that occurs at the beginning of the laser pulse. This raises the radiation temperature in the foot or trough period of the pulse (hence the name "high-foot" pulse), increasing the stability of the ablator but reducing compression later in the implosion.
The high-foot campaign was born after systematically exploring possible causes for the shell breakup observed in a series of lower foot, more compressed experiments, and developing hypotheses for how to address the issue.
"In the spirit of what Livermore is good at, this work was born out of the fierce competition of ideas of how to fix the problem, but then coming together as a team to move the best ideas forward," said Omar Hurricane, lead scientist on the campaign. "In this particular experiment, we intentionally lowered the goal in order to gain control and learn more about what Mother Nature is doing. The results were remarkably close to simulations and have provided an important tool for understanding and improving performance."
These promising returns were the result of a laser experiment that delivered 1.7 megajoules (MJ or million joules) of ultraviolet light at 350 terawatts (TW or trillion watts) of peak power. NIF is the world's largest and most energetic laser system, which has already pushed past its design specifications of 1.8 MJ and 500 TW, leaving headroom for more exploration of this idea.
It's not clear what the difference between these experiments is, but in any case, in the last month and a half, ignition became within the project's reach...The BBC understands that during an experiment in late September, the amount of energy released through the fusion reaction exceeded the amount of energy being absorbed by the fuel - the first time this had been achieved at any fusion facility in the world.
This is a step short of the lab's stated goal of "ignition", where nuclear fusion generates as much energy as the lasers supply. This is because known "inefficiencies" in different parts of the system mean not all the energy supplied through the laser is delivered to the fuel.