Least-squares fit analysis program for the evaluation of spatially resolved x-ray spectra from tokamak plasmas

A least-squares fit analysis program is being developed for the study of spatially resolved x-ray spectra from tokamak plasmas. The program, written in interactive data language, can handle analysis of spectra from multiple sightlines through the plasma and compare the experimental data with a least-square fit of synthetic spectra, which are constructed from atomic modeling codes. The input parameters such as shot numbers, time groups, spatial range, spectral lines to fit and fitting parameters can be entered interactively through a graphical user interface or automatically via a script. The output consists of graphical presentations of the obtained spectral fits and fit parameter profiles as a function of time, including ion and electron temperature profiles, which are of particular interest. Output can also be sent to any open database connectivity compliant database. The features of the program are demonstrated with the analysis of the spectra of helium-like ArXVII, which were obtained with a new x-ray imaging crystal spectrometer