A 'shot' that can change the worldFifteen years of work by the Lawrence Livermore National Laboratory's National Ignition Facility (NIF) team paid off on July 5 with a historic record-breaking laser shot. The NIF laser system of 192 beams delivered more than 500 trillion watts (terawatts or TW) of peak power and 1.85 megajoules (MJ) of ultraviolet laser light to its target. Five hundred terawatts is 1,000 times more power than the U.S. uses at any instant in time, and 1.85 megajoules of energy is about 100 times what any other laser regularly produces today.
That's quite an accomplishment, especially considering that it was just a few years ago that many of us stood in the hot summer sun as the Lab and local and national political representatives joined in dedicating the sophisticated, high tech facility that made this possible. Of course, more is yet to come as scientists continue the pursuit for fusion, a technology that will make energy renewal endless.
Still, the shot validated NIF's most challenging laser performance specifications set in the late 1990s when scientists were planning the world's most energetic laser facility. Combining extreme levels of energy and peak power on a target in the NIF is a critical requirement for achieving one of physics' grand challenges -- igniting hydrogen fusion fuel in the laboratory and producing more energy than that supplied to the target.
In the historic test, NIF's 192 lasers fired within a few trillionths of a second of each other onto a 2-millimeter-diameter target. The total energy matched the amount requested by "shot" managers to within better than 1%. Additionally, the beam-to-beam uniformity was within 1%, making NIF not only the highest energy laser of its kind but the most precise and reproducible. "NIF is becoming everything scientists planned when it was conceived over two decades ago," NIF Director Edward Moses told supporters at a congratulatory ceremony last week.
Now that this process is fully operational, scientists are taking important steps toward achieving ignition and providing experimental access to user communities for national security, basic science and the quest for clean fusion energy.