Ultra-heated plasma safety net | EOS Science

Nuclear fusion, the process by which atomic nuclei generate vast amounts of heat, remains the ultimate dream of an inexhaustible energy source. That’s why fusion scientists at Cadarache in southern France are still hard at work on the ITER experimental fusion reactor. According to the latest planning, it should be ready by the end of 2025. The first tests can finally begin. In a cake-shaped ITER reactor, called a tokamak, hot fusion plasma of 150 million degrees is trapped in a magnetic cage.

But fusion experts are concerned that the cage isn’t completely watertight and that particles could escape. If this happens at high speed and the particles hit parts of the reactor wall that they cannot withstand, serious problems can arise. That’s why physicists have long been looking for ways to trap plasma particles – especially electrons – before they can escape the plasma and cause damage. Now a team of European and American researchers has succeeded in doing so. He has developed a technique that allows him to capture “disjointed electrons” moving near the speed of light before exiting the plasma.

This technique relies on injecting chilled deuterium ‘pull’ into the plasma. Deuterium is a heavy isotope of hydrogen. Deuterium will be injected into ITER through about thirty orifices around the 30-meter-wide reactor. In this way, the released electrons can be stopped in time.

Brun: EUROFusion