Sawtooth Swings In Fusion Plasma Stabilized
Up-and-down ripples, swings that rise and recede like the teeth on a saw blade, are found in everything from stock prices on Wall Street to ocean waves; and they occur periodically in the temperature and density of the plasma that fuels fusion reactions in doughnut-shaped facilities called tokamaks. If the swings combine with other instabilities in the plasma they can halt the reactions. Why some plasmas are free of sawtooth gyrations has long puzzled physicists.
Fusion, the power that drives the sun and stars, is the fusing of light elements in the form of plasma -- the hot, charged…