Livermore scientists report that after years of experiments, they have moved closer to reproducing the blazing energy of the sun’s interior in the laboratory.
A team of physicists and engineers at the $3.5 billion National Ignition Facility said they fired an array of 192 laser beams, focused “in perfect unison,” and created a single pulse of energy that for 23 billionths of a second generated a thousand times more power than the entire United States consumes in a single second.
The experiment March 15 delivered to the center of the facility’s target chamber 1.87 megajoules of ultraviolet light, amounting to 100 times more energy than any other laser system in the world, the scientists said in a report.
A megajoule is a million joules of energy, the equivalent of a million watts of electric power. In this one experiment, the virtually instantaneous shot generated 411 trillion watts of power, the scientists said.
The ultimate goal of the multibillion-dollar laboratory experiments is to safely mimic in miniature the immensely powerful thermonuclear explosions of hydrogen bombs so that experts can validate their bomb-making computer codes and verify the safety and reliability of America’s arsenal of nuclear weapons.
To achieve that kind of explosion, the facility’s 192 laser beams would have to be focused so precisely and be delivered at such immensely high energy that the combined single beam would crush a tiny capsule of frozen hydrogen gas no bigger than a peppercorn and ignite a thermonuclear reaction inside the capsule.
In nature those reactions are known only in the interior of the sun and the stars, and the physics involved is so difficult that it demands far more megajoules of energy than has so far been reached. At the start of the experiments two years ago, the scientists’ goal was an energy beam of only a single megajoule, but in shot after shot energy has increased slowly.