PPPL-5043


<p>Access to a New Plasma Edge State with High Density and Pressures using Quiescent H-mode</p>
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<b>Authors:</b><span class="author"> W.M. Solomon, P.B. Snyder, K.H. Burrell, M.E. Fenstermacher, A.M. Garofalo, B.A. Grierson, A. Loarte, G.R. McKee, R. Nazikian, and T.H. Osborne</span></p>
<p><b>Abstract:</b> A path to a new high performance regime has been discovered in tokamaks that could improve the attractiveness of a fusion reactor. Experiments on DIII-D using a quiescent H-mode edge have navigated a valley of improved edge peeling-ballooning stability that opens up with strong plasma shaping at high density, leading to a doubling of the edge pressure over standard edge localized mode (ELM)ing H-mode at these parameters. The thermal energy confinement time increases both as a result of the increased pedestal height and improvements in the core transport and reduced low-<em>k</em> turbulence. Calculations of the pedestal height and width as a function of density using constraints imposed by peeling-ballooning and kinetic-ballooning theory are in quantitative agreement with the measurements.<br>
    
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<b>Accepted for publication in: </b>Physical Review Letters<br>
  
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  <a href="PPPL-5043.pdf"><b>Download PPPL-5043</b></a> (pdf 1.4 MB; 15pp)
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