An extended formulation for efficiently calculating the stability of edge localized modes, which includes the effects of current as well as pressure, has been developed in collaboration with H.R. Wilson of Culham Science Centre. The new calculation extends the high n expansion used in the ELITE code up to order 1/n. This extension allows new physics by including instability drive from the radially extended edge current profile; previously the lower order expansion only included the drive from an edge surface current. The expanded formulation will be included in the ELITE code and should allow fully quantitative comparisons with GATO. The ELITE code will then be used for calculations of ELM stability in DIII-D.
These highlights are reports of research work in progress and are accordingly subject to change or modification