High-resolution multiposition Thomson scattering for the TJ-II stellarator

In this article, the recent installed multiposition Thomson scattering (TS) of the TJ-II stellarator is presented. Light from a pulsed ruby laser is scattered by the free electrons of the plasma and led to a spectrometer for spectral analysis. The Doppler broadened spectrum of the scattered light is analyzed with a spectrometer in the Littrow configuration, detected with a GaAsP image intensifier and recorded with two intensified charged coupled device cameras. Values of the electron temperature (T-e) in the range of 50 eV up to 4 keV can be measured at 160 spatial elements of 2.25 mm along a chord of 360 mm. First results show that the observational error for T-e is close to the expected error of similar to 10% at an electron density (n(e)) of 1 X 10(19) m(-3) using a laser energy of 8 J. (C) 1999 American Institute of Physics. [S0034-6748(99)64101-6].