American Institute of Physics, Physics of Plasmas, 1(24), p. 012504
DOI: 10.1063/1.4972822
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Methods are described that extend fields from reconstructed equilibria to include scrape-off-layer current through extrapolated parametrized and experimental fits. The extrapolation includes both the effects of the toroidal-field and pressure gradients which produce scrape-off-layer current after recomputation of the Grad-Shafranov solution. To quantify the degree that inclusion of scrape-off-layer current modifies the equilibrium, the $χ$-squared goodness-of-fit parameter is calculated for cases with and without scrape-off-layer current. The change in $χ$-squared is found to be minor when scrape-off-layer current is included however flux surfaces are shifted by up to 3 cm. The impact on edge modes of these scrape-off-layer modifications is also found to be small and the importance of these methods to nonlinear computation is discussed. ; Comment: 14 pages