Measurements of n e(r) and T e(r) in TdeV boundary layer by injection of laser ablated Li and C

Li-atom and C-atom beams with energies of 5 and 15 eV, respectively, have been used to measure the electron density and temperature profiles in the scrape off layer and the plasma edge in TdeV. The beam penetrates into the plasma up to line densities of about nel=3×1017 m−2 and allows an instantaneous (≊250 μs) measurement of ne and Te up to 1.5×1019 m−3 and 100 eV, respectively. A camera with a Si-diode array is used to determine the spatial emissivity of the emitted light. Te(r) and ne(r) are obtained from the different attenuation and emission characteristics over the spatial range from the wall to ≊50 mm within the separatrix.