Figures of merit for stellarators near the magnetic axis

  title={Figures of merit for stellarators near the magnetic axis},
  author={Matt Landreman},
  journal={Journal of Plasma Physics},
  • M. Landreman
  • Published 1 December 2020
  • Physics
  • Journal of Plasma Physics
A new paradigm for rapid stellarator configuration design has been recently demonstrated, in which the shapes of quasisymmetric or omnigenous flux surfaces are computed directly using an expansion in small distance from the magnetic axis. To further develop this approach, here we derive several other quantities of interest that can be rapidly computed from this near-axis expansion. First, the $\boldsymbol {\nabla }\boldsymbol {B}$ and $\boldsymbol {\nabla }\boldsymbol {\nabla }\boldsymbol {B… 

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