The sun defies conventional scientific understanding. Its upper atmosphere, known as the corona, is many millions of degrees hotter than its surface. Astrophysicists are keen to learn why the corona is so hot, and scientists at the U.S. Department of Energy’s (DOE) Princeton Plasma Physics Laboratory (PPPL) have completed research that may advance the search.…
Surprise Finding: Discovering a Previously Unknown Role for a Source of Magnetic Fields
Magnetic forces ripple throughout the universe, from the fields surrounding planets to the gasses filling galaxies, and can be launched by a phenomenon called the Biermann battery effect. Now scientists at the U.S. Department of Energy’s (DOE) Princeton Plasma Physics Laboratory (PPPL) have found that this phenomenon may not only generate magnetic fields, but can…
Protecting the Power Grid: Advanced Plasma Switch for More Efficient Transmission
Inside your home and office, low-voltage alternating current (AC) powers the lights, computers and electronic devices for everyday use. But when the electricity comes from remote long-distance sources such as hydro-power or solar generating plants, transporting it as direct current (DC) is more efficient — and converting it back to AC current requires bulky and…
No More Zigzags: Scientists Uncover Mechanism That Stabilizes Fusion Plasmas
Sawtooth swings — up-and-down ripples found in everything from stock prices on Wall Street to ocean waves — occur periodically in the temperature and density of the plasma that fuels fusion reactions in doughnut-shaped facilities called tokamaks. These swings can sometimes combine with other instabilities in the plasma to produce a perfect storm that halts…
Scientists Improve Ability to Measure Electrical Properties of Plasma
Any solid surface immersed within a plasma, including those in satellite engines and fusion reactors, is surrounded by a layer of electrical charge that determines the interaction between the surface and the plasma. Understanding the nature of this contact, which can affect the performance of the devices, often hinges on understanding how electrical charge is…
Physicist Discovers That Some Plasma Instabilities Can Extinguish Themselves
Physicist Fatima Ebrahimi at the U.S. Department of Energy’s (DOE) Princeton Plasma Physics Laboratory (PPPL) has for the first time used advanced models to accurately simulate key characteristics of the cyclic behavior of edge-localized modes (ELMs), a particular type of plasma instability. The findings could help physicists more fully comprehend the behavior of plasma, the…
New Model of Plasma Stability Could Help Researchers Predict and Avoid Disruptions
Physicists at the U.S. Department of Energy’s (DOE) Princeton Plasma Physics Laboratory (PPPL) have helped develop a new computer model of plasma stability in doughnut-shaped fusion machines known as tokamaks. The new model incorporates recent findings gathered from related research efforts and simplifies the physics involved so computers can process the program more quickly. The…