A visible spectroscopic imaging system has been developed on Tokamak de Var
ennes (TdeV) that provides profile measurements of the ion temperature and
plasma rotation velocity. Multiple poloidal and tangential chords were coup
led to the entrance slit of a spectrometer equipped with a back-illuminated
charge coupled device camera at its exit slit. The camera records spatiall
y and spectrally resolved emission profiles with real time digitization and
up to 70 ms/frame as temporal resolution. Line-integrated radiation from d
ifferent ionization stages in the visible range (B V, C III, He II, and N I
V) were chosen as representative of the plasma in their regions of maximum
emission. Three types of plasma discharges are compared: ohmic and electron
cyclotron resonance heated L and H modes. Preliminary results show that wi
th an L-H transition, there is a 20%-30% increase of the ion temperature at
midradius, without a pedestal and an increase of the toroidal velocity she
ar at r/alpha similar to 0.8. (C) 1999 American Institute of Physics. [S003
4-6748(99)57101- 3].