Edge turbulence measurements in TFTR

Turbulent fluctuations and confinement in JET

“…different elongation, horizontal position, Z e ff. Similar trends were already reported in previous papers [1][2][3][4]20] and can also be observed in Figs 3, 20, 21 and 22 for different pulses.…”

“…12). Although fluctuations in the emitted radiation are not easily ascribed to any of the various plasma parameters, some indications from other experiments point at n e as the most likely candidate: fast time resolved images from a visible camera in NBI heated TFTR discharges show edge fluctuations of H a radiation that are in all respects similar to our results [20] and confirm earlier measurements on ASDEX [21 ]. Although the above measurements are, by the nature of the diagnostics, limited to still relatively long wavelength fluctuations, they should be considered complementary to those of finer structure n e -data obtained, e.g.…”

High-speed 2-D image measurement for plasma-wall interaction studies

“…Striped patterns were first observed on the inner wall of the TFTR vacuum vessel using a fast video camera, and these observations were attributed to edge plasma turbulence [1]. Recently a more sophisticated way to visualize edge plasma turbulence was developed in Cmod and NSTX [2,3], referred to as Gas Puff Imaging (GPI).…”

Marfes from radiative condensation instability of electrostatic drift waves in tokamak edge plasmas

“…Since the density and temperature gradients are large in edge plasmas where the fluctuations are usually dominated by those in the perpendicular (to the external field B) direction, we consider, in this letter, the linear coupling of electrostatic drift waves to the radiation mode. Drift wave or drift wave-like fluctuations are always observed at tokamak edges and are believed to be responsible for edge transport [11][12][13][14][15][16][17][18][19]. It is, therefore, of practical interest to consider their interaction with the thermal radiation instability.…”

“…(10). cross-field particle and heat fluxes because both the density perturbation Bel = 0) (18) and the temperature perturbation f _ T e l ~7=:…”