1. Long pulse high beta discharges with normalised beta larger than 3 have been sustained for up to 4 seconds. 2. MHD activity at high beta is due to ELMs, fishbones and continuous n=1 and n=2 modes in the plasma centre. 3. NO ν~* (collisionality) dependence found of the beta limit in JET. 4. (so far) NO neo-classical tearing modes observed in JET high beta discharges. 5. This may be due to the absence of sawteeth (or long sawtooth free period), i.e no seed island is created. Even though there are ELMs and fishbones which can in principle create seed islands.
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