Deconvolution of Thomson scattering temperature profiles

Scannell, R.; Beurskens, M.; Carolan, P. G.; Kirk, A.; Walsh, M.; O'Gorman, T.; Osborne, T. H.
May 2011
Review of Scientific Instruments;May2011, Vol. 82 Issue 5, p053501
Academic Journal
Deconvolution of Thomson scattering (TS) profiles is required when the gradient length of the electron temperature (Te) or density (ne) are comparable to the instrument function length (ΔR). The most correct method for deconvolution to obtain underlying Te and ne profiles is by consideration of scattered signals. However, deconvolution at the scattered signal level is complex since it requires knowledge of all spectral and absolute calibration data. In this paper a simple technique is presented where only knowledge of the instrument function I(r) and the measured profiles, Te, observed(r) and ne, observed(r), are required to obtain underlying Te(r) and ne(r). This method is appropriate for most TS systems and is particularly important where high spatial sampling is obtained relative to ΔR.


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