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In order to characterize the Madison Symmetric Torus (MST) reversed-field pinch (RFP) plasmas that bifurcate to a helical equilibrium, the V3FIT equilibrium reconstruction code was modified to include a conducting boundary. RFP plasmas become helical at a high plasma current, which induces large eddy currents in MST's thick aluminum shell. The V3FIT conducting boundary accounts for the contribution from these eddy currents to external magnetic diagnostic coil signals. This implementation of V3FIT was benchmarked against MSTFit, a 2D Grad-Shafranov solver, for axisymmetric plasmas. The two codes both fit B h measurement loops around the plasma minor diameter with qualitative agreement between each other and the measured field. Fits in the 3D case converge well, with q-profile and plasma shape agreement between two distinct toroidal locking phases. Greater than 60% of the measured n ¼ 5 component of B h at r ¼ a is due to eddy currents in the shell, as calculated by the conducting boundary model. V

Affinity and difference between energetic-ion-driven instabilities Ya I Kolesnichenko, A Könies, V V Lutsenko et al. Excitation of the beta-induced Alfvén eigenmode by a plasma flow around the magnetic island