Detailed new H-mode pedestal measurements in the inter-ELM periods of DIII-D discharges find that ion temperature gradient (ITG)-scale density fluctuations (รฑ) can explain anomalous ion heat flux (Q$_{i}$) during the ELM (Fig. [1]), followed by Q$_{i}$ becoming neo-classical$^{1}$ until the next ELM, and with trapped electron mode (TEM) and microtearing mode (MTM) like รฑ and magnetic...
Since the initial JET operations with the metal wall (JET-ILW), the experimental results have shown a pedestal pressure in baseline plasmas that tends to be 10-20% lower than in the corresponding earlier carbon wall operations (JET-C) [1]. While this degradation seems mainly correlated with the high fueling rates typical of JET-ILW [2,3] and/or the lack of carbon impurity [4,5], an exhaustive...
$\qquad$ Characterizing and understanding the power threshold conditions for ITER to achieve H-modes ($P_{LH}$) is a major goal of a series of L-H transition experiments undertaken at JET since the installation of the ITER-like-wall (JET-ILW), with Beryllium wall tiles and Tungsten divertor [1,2,3,4]. In this contribution we report on results from L-H transitions studies in H, D and new almost...
Sudden increase of the energy confinement time by 38% is observed during divertor detachment operation with RMP application in deuterium plasmas in LHD. Edge transport barrier (ETB) is formed during the RMP induced H-mode phase at the inner separatrix of magnetic island created by the RMP, leading to steepening of pressure profile while the detachment is maintained. Such behavior has been...
Due to the limited power exhaust capability of the divertor, a future DEMO reactor needs a high core/pedestal radiation level, controlled and tailored by an appropriate seed impurity mix. The core/pedestal seeding has to be integrated with substantial divertor radiative cooling and a no/very small ELM plasma regime. Required boundary conditions of the seeding scenario are sufficient energy...
An optimized pedestal regime called the Super-H Mode (SH-mode) is leveraged to simultaneously couple a fusion relevant core plasma with a scrape-off layer appropriate for realistic reactor exhaust solutions. Recent DIII-D experiments have expanded the operating space from previous studies of the SH regime and investigated optimization of impurity seeding, deuterium gas puffing, 3D magnetic...
