Extending the Physics Basis of Quiescent H-mode toward ITER Relevant Parameters
Authors: W.M. Solomon, K.H. Burrell, M.E. Fenstermacher, A.M. Garofalo, B.A. Grierson, A. Loarte, G.R. McKee, R. Nazikian, and P.B. Snyder
Abstract: Recent experiments on DIII-D have overcome a long-standing limitation in accessing quiescent H-mode (QH-mode), a high confinement state of the plasma that does not exhibit the explosive instabilities associated with edge localized modes (ELMs). In the past, QH-mode was associated with low density operation, but has now been extended to high normalized densities compatible with operation envisioned for ITER. Through the use of strong shaping, QH-mode plasmas have been maintained at high densities, both absolute (¯ne ≈ 7 × 1019 m−3) and normalized Greenwald fraction (¯ne/nG > 0.7) . In these plasmas, the pedestal can evolve to very high pressures and current as the density is increased.
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Presented at: the 25th IAEA Fusion Energy Conference, St. Petersburg, Russia, 13-18 October 2014.
Submitted to: Nuclear Fusion
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