Rotation reversal bifurcation and energy confinement saturation in tokamak Ohmic L-mode plasmas.
نویسندگان
چکیده
Direction reversals of intrinsic toroidal rotation have been observed in diverted Alcator C-Mod Ohmic L-mode plasmas following electron density ramps. For low density discharges, the core rotation is directed cocurrent, and reverses to countercurrent following an increase in the density above a certain threshold. Such reversals occur together with a decrease in density fluctuations with 2 cm(-1)≤k(θ)≤11 cm(-1) and frequencies above 70 kHz. There is a strong correlation between the reversal density and the density at which the Ohmic L-mode energy confinement changes from the linear to the saturated regime.
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ورودعنوان ژورنال:
- Physical review letters
دوره 107 26 شماره
صفحات -
تاریخ انتشار 2011