Experimental evidence of significant temperature fluctuations in the plasma edge region of the TJ-I tokamak

Density and temperature fluctuations have been measured in the plasma bulk side of the velocity-shear location of the TJ-I tokamak using a fast swept Langmuir probe technique. Evidence has been found that substantial temperature fluctuations have a phase difference of close to ψ with respect to the corresponding density fluctuations. This result suggests the possible role of radiation in determining edge fluctuation levels and calls into question the determination of the density and potential fluctuations from the Langmuir current probe and floating potential fluctuations.