Absolute Sensitivity Calibration of Visible Spectroscopic Diagnostic and Temporal Evolution of First Window Transmittance at the COMPASS Tokamak
2013
Abstract
An absolute calibration of spectroscopic systems is required to measure many important plasma parameters in tokamak discharges like impurity inflow, recycling and the effective ion charge. The procedure of the absolute calibration is described and technical issues and experimental limitations connected with the tokamak operation are discussed here.
Namely, an influence of the first window transmittance and its evolution over experimental campaigns on the validity of the absolute calibration is investigated.