An international team of scientists including Czech experts from the Institute of Plasma Physics of the CAS explored a new method to mitigate the runaway electron beam, based on the recent experiments at the largest European tokamak JET (Culham Centre for Fusion Energy, UK). The paper reporting these results was published in the prestigious scientific journal Physical Review Letters (PRL).
In the case that such a beam will be generated during a sudden cooling of the plasma, we need to be ready with a specific scenario to mitigate its kinetic energy. So far, namely injection of the heavy noble gases has been used for this purpose. However, the new experiments show that the opposite – injection of increased amount of hydrogen/deuterium in the form of frozen pellets – leads to spontaneous decay of the beam without any noticeable damage to the wall.
3 May 2021