The National Ignition Facility at Lawrence Livermore National Laboratory is gearing up for its first target experiments with all 192 laser beams in May.
According to NIF project director Ed Moses, the massive facility is fully operational, but "we don't like to use the word 'finished.'" Moses said the preferred term is "fully commissioned and just beginning."
The facility conducted target experiments as far back as 2001 with just a few beams, and in January of this year with 96 beams. On February 26, the first 192-beam system shot to the center of the National Ignition Facility Target Chamber was fired, marking the unofficial completion of the NIF construction project.
Moses described the amplification process the NIF uses to generate the power it will need to conduct its fusion experiments: "We have two amplifier banks, one with 11 slabs of glass in it, the other with five - that's called the 11-5 configuration. If you look at how many times they pass back and forth through the glass, you have 54 single-pass slab amplifications. So it goes from nanojoules in a beam where we start, through a preamplifier where it goes through 100 millijoules, then up to the big amplifiers and it comes out at 20-ish kilojoules in the infrared. Then we double it, triple it, at around 50 percent efficiency, and we have 10 kilojoules of ultraviolet light per beam - 192 comes out to almost two megajoules of energy on targets."
The NIF has three primary missions - national security, energy for the future, and understanding the universe. Moses highlighted the benefits of being able to create conditions to study fusion reactions in lieu of weapons testing, experiment with a potential source of energy, or study the cosmos in the NIF target chamber.
"Some pretty far out stuff can be done on the NIF, so instead of having to look through our beautiful telescopes and inferring what's going on, we'll be able to assemble a small supernova - very small - inside the target chamber on schedule, have all your diagnostics in place, and fire it away and study it."
Numerous technologies are expected to spin off from all the development work that has been done on the project. Moses cited optics used for NIF components as one area where the project has already made a big impact. "I think that over time these things will just be spreading more and more," he said.
Moses gave credit to the nearly 3000 partners that worked on the facility. He said they included machine shops, architects, engineers, construction companies, "and of course the optics industry. We worked with many of the big optics industry vendors in partnership to build these really superior glass components." The NIF includes 7000 single pieces of large optics. "When we talk about large optics, we mean 40-centimeter apertures. And there are over 30,000 small optics, which is generally under 10 centimeters."
Dignitaries from around the world are expected at the NIF dedication ceremony on May 29.
Moses is a Fellow of SPIE. He was interviewed for SPIE Newsroom on March 23.
Ed Moses/National Ignition Facility video podcast (MP4) | QuickTime video
National Ignition Facility website: https://lasers.llnl.gov/