Scale length of microturbulence in tokamak plasmas.

This Comment considers the dependence of the density fluctuation spectrum observed in tokamak plasmas on the parameters of the plasma. Experimental evidence to date indicates that the width, DELTA k, of the wavenumber spectrum is proportional to magnetic field but appears to be insensitive to the plasma temperature. The quantity (DELTA k) sup -1 is the correlation length of the fluctuations, and therefore determines the spatial scale of the turbulence.