Structures in T-e profiles: High resolution Thomson scattering in the Rijnhuizen tokamak project

In the Rijnhuizen tokamak project, the double pulse multiposition Thomson scattering diagnostic is in full operation. Its high spatial resolution enables the measurement of small scale structures in T-e, n(e), and p(e). Thomson scattering profiles during an ordinary sawtooth crash show the displacement of the hot core in great detail. Measurements on off-axis sawtoothing plasmas show that a small central part remains unaffected. Filaments are observed in plasmas which show a transient central temperature rise in response to fast edge cooling. (C) 1999 American Institute of Physics. [S0034-6748(99)67601-8].