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# Disruption prediction with artificial intelligence techniques in tokamak plasmas

## Abstract

In nuclear fusion reactors, plasmas are heated to very high temperatures of more than 100 million kelvin and, in so-called tokamaks, they are confined by magnetic fields in the shape of a torus. Light nuclei, such as deuterium and tritium, undergo a fusion reaction that releases energy, making fusion a promising option for a sustainable and clean energy source. Tokamak plasmas, however, are prone to disruptions as a result of a sudden collapse of the system terminating the fusion reactions. As disruptions lead to an abrupt loss of confinement, they can cause irreversible damage to present-day fusion devices and are expected to have a more devastating effect in future devices. Disruptions expected in the next-generation tokamak, ITER, for example, could cause electromagnetic forces larger than the weight of an Airbus A380. Furthermore, the thermal loads in such an event could exceed the melting threshold of the most resistant state-of-the-art materials by more than an order of magnitude. To prevent disruptions or at least mitigate their detrimental effects, empirical models obtained with artificial intelligence methods, of which an overview is given here, are commonly employed to predict their occurrence—and ideally give enough time to introduce counteracting measures.

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## Acknowledgements

This work was partially funded by the Spanish Ministry of Science and Innovation under projects nos. PID2019-108377RB-C31 and PID2019-108377RB-C32. This work has been carried out within the framework of the EUROfusion Consortium, funded by the European Union via the Euratom Research and Training Programme (grant agreement no. 101052200 — EUROfusion). Views and opinions expressed are however those of the authors only and do not necessarily reflect those of the European Union or the European Commission. Neither the European Union nor the European Commission can be held responsible for them.

## Author information

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Correspondence to J. Vega.

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The authors declare no competing interests.

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Nature Physics thanks Cristina Rea and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.

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Vega, J., Murari, A., Dormido-Canto, S. et al. Disruption prediction with artificial intelligence techniques in tokamak plasmas. Nat. Phys. 18, 741–750 (2022). https://doi.org/10.1038/s41567-022-01602-2

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• DOI: https://doi.org/10.1038/s41567-022-01602-2