Reconstruction of plasma edge density profiles from Li I (2s-2p) emission profiles

Abstract

The injection of 10-100 keV Li0 diagnostic beams into magnetically confined fusion plasmas causes collisionally induced Li I emission at 670.8 nm, in close relation to the edge plasma electron density. A numerical method for quantitative reconstruction of the plasma density exclusively from relative Li I 670.8 nm emission profiles as measured along the diagnostic beam has been developed, involving all relevant collisional interactions of the Li atoms with plasma constituents. The applicability of the described algorithm is illustrated by experimental results obtained for the TEXTOR Tokamak edge plasma at KFA Julich.