New issue of ASDEX Upgrade Newsletter
Information on research with the ASDEX Upgrade fusion device
ASDEX Upgrade Letter deals with present developments and research results from the ASDEX Upgrade tokamak fusion device at Garching, on which scientists from all over Europe are working.
Issue 22/2020 features, inter alia, how instabilities at the plasma edge, so-called "edge localised modes" (ELMs), can be avoided. Without the eruptive ELMs, which in large devices would put great strain on the vessel wall, a power exhaust in a more gentle, quasi-continuous manner is desired. As experiments on ASDEX Upgrade show, the conditions for the onset of ELMs can be favourably influenced by altering the plasma edge.
Furthermore, the injection of pulverised boron into the plasma was investigated at ASDEX Upgrade in collaboration with the US fusion laboratory in Princeton. A thin boron film on the vessel walls can absorb impurities. For coating, however, the magnetic field has so far had to be switched off – unfavourable for facilities with superconducting magnetic coils such as ITER or Wendelstein 7-X. However, the powder method works without switching off the magnetic fields.