“A major breakthrough in nuclear fusion has been confirmed a year after it was achieved in a California lab,” reports Newsweek:
On August 8, 2021, researchers at Lawrence Livermore National Laboratory’s National Ignition Facility recorded the first case of ignition, the results of which have now been published in three peer-reviewed papers….
Ignition during a fusion reaction essentially means that the reaction itself has produced enough energy to be self-sustaining, which would be necessary if fusion were used to produce electricity. If we could use this reaction to produce electricity, it would be one of the most efficient and least polluting sources of energy. No fossil fuel would be needed as the only fuel would be hydrogen and the only by-product would be helium which we use in industry and which is actually in short supply….
This landmark result comes after years of research and thousands of man-hours dedicated to improving and perfecting the process: more than 1,000 authors are included in the Physical Review Letters paper.
The lab said this week that the breakthrough now puts researchers “on the brink of enhancing fusion and achieving scientific ignition,” with the program’s chief scientist calling it “an important scientific advance in fusion research that shows that fusion ignition is possible in the laboratory at the National Factory ignition”.
More news from this week’s Lawrence Livermore National Laboratory announcement:
After the experiment last August, the team conducted a series of experiments to try to replicate the performance and understand the experimental sensitivity in this new regime. “Many variables can affect each experiment,” Critcher said. “The 192 laser beams do not perform the same from shot to shot, the quality of the targets varies, and the ice layer grows at different roughnesses on each target…”
Although the repeat attempts did not achieve the same level of fusion yield as the August 2021 experiment, they all demonstrated capsule growth greater than unity with yields in the 430-700 kJ range, significantly higher than than the previous highest output of 170 kJ from February 2021. The data from these and other experiments provide important clues about what went right and what changes are needed to repeat this experiment and exceed its performance in the future. The team is also using experimental data to further understand the fundamental processes of fusion ignition and combustion and to improve modeling tools to support inventory management.
Looking ahead, the team is working to use the accumulated experimental data and simulations to move to a more robust regime—beyond the ignition cliff—where the general trends revealed in this new experimental regime can be better separated from target variability and laser performance. Efforts are underway to improve the performance and durability of fusion reactors. This includes improving the compression of the fusion fuel, increasing the amount of fuel and other possibilities.
“It’s very exciting to have ‘proof of existence’ of ignition in the lab,” said Omar Hurricane, chief scientist of the lab’s fusion program. “We’re working in a mode that no researchers have had access to since the end of nuclear testing, and this is an incredible opportunity to expand our knowledge as we continue to make progress.”
Thanks to longtime Slashdot reader hesdeadjim99 for sharing the news.