The effect of plasma beta on high-n ballooning stability at low magnetic shear

@article{Connor2016TheEO,
  title={The effect of plasma beta on high-n ballooning stability at low magnetic shear},
  author={J. W. Connor and C J Ham and R. J. Hastie},
  journal={Plasma Physics and Controlled Fusion},
  year={2016},
  volume={58}
}
An explanation of the observed improvement in H-mode pedestal characteristics with increasing core plasma pressure or poloidal beta, βpol, as observed in MAST and JET, is sought in terms of the impact of the Shafranov shift, Δ′, on ideal ballooning MHD stability. To illustrate this succinctly, a self-consistent treatment of the low magnetic shear region of the ‘s−α’ stability diagram is presented using the large aspect ratio Shafranov equilibrium, but enhancing both α   and Δ′ so that they… 

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