Equilibrium reconstruction using Faraday-effect polarimetric measurements on DIII-D

Measurements from the Radial Interferometer-Polarimeter (RIP) on DIII-D provide new constraints (three chords of Faraday-effect and density) into the plasma internal magnetic profile. Integration of these measurements into the EFIT Grad-Shafranov equilibrium fitting code will add further constraints on the targeted equilibrium and enable more accurate reconstruction of the plasma behavior, especially for plasmas where MSE is not available. The ongoing implementation of these constraints into EFIT is presented, as are results of the modified equilibrium fitting, demonstrating the influence of the inclusion of RIP measurements on the calculated equilibria. Comparisons between RIP and MSE constraints for equilibrium construction are presented, including on measures of q0 on-axis and on evolution during discharge, as are measures of uncertainty and explorations of scenario dependence. As Faraday-Effect polarimetry will be used on ITER, understanding its application will be important for diagnosis and control of future burning plasma reactors.