Video Diagnostics
Plasma Physics

Group leader: Tamás Szepesi

The website of the group:

Our group is focusing on the understanding of the interaction between the 10 million °C hot plasma and -270 °C solidified Hydrogen balls, the pellets. Pellets are injected into the plasma at high speeds (>1000 km/h) in order to replenish the fuel in a fusion reactor – this is the best way to deposit fuel in the hot and dense center of the plasma. Our investigations aim at maximizing the fuelling efficiency of pellets, i.e. to find ways to deposit a significant fraction of the pellet material in the plasma core.

Pellets can also be used to tailor plasma instabilities called ELMs, which could even harm reactor components – without control. By using ultra fast cameras producing up to 1 million images per second, we are investigating the ELM tailoring capability of the pellets. Our aim is to understand this physics process and then extend the applicability of the pellet-ELM controlling technique from present fusion experiments to future, power plant sized machines.

Our scientists are involved in Europe’s leading fusion experiments: the ASDEX Upgrade tokamak in Germany, the JET tokamak in the UK, and also at the “world’s most complicated fusion experiment”, the Wendelstein 7-X stellarator. The investigations at these devices are also supported by own developments: a portable pellet injector ‘TATOP’ is being developed to study the interaction of non-fuelling material pellets with the plasma; a special fast camera ‘EDICAM’ was also developed by our team to fulfill the need of modern fusion experiments, such as real-time image processing, intelligent image-based feedback control and extending the applicability of fast cameras from seconds to hours.