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A 10 J ruby laser Thomson scattering system was implemented on the ETE spherical tokamak to measure the density n[sub e] and temperature T[sub e] profiles. The laser probes the plasma at the horizontal midplane of the torus and the collection optics allows the observation of up to 22 points inside the plasma in the same plane. Radial profiles of plasma density and electron temperature were obtained for different times during the discharge by shot-to-shot procedure. Temperatures of up to 160 eV and densities of 2.2 × 10[sup 19] m[sup -3] were measured. Since the level of stray light was too high, the calibration of the Thomson scattering system for density measurements was made using the nitrogen Raman technique instead of the usually applied Rayleigh method. [ABSTRACT FROM AUTHOR]

To measure the electron temperature and plasma density profiles on the Experimento Tokamak Esférico tokamak a multiplexed Thomson scattering diagnostic was implemented. The diagnostic is based on a 10 J ruby laser and a single five spectral channel filter polychromator. A collection lens with f/6.3 relay the scattered light from 23 spatial points to optical fibers. The fibers have a monotonous increasing length and are inserted into the polychromator. Between the collection lens and each fiber optic we have a microlens to match the numerical aperture and to enlarge the plasma observation volume. This work describes the project, the simulations, and the preliminary results obtained with the first four optical fibers. [ABSTRACT FROM AUTHOR]