TECHNIQUES FOR DERIVING DOPPLER TEMPERATURES FROM MULTIPLE-LINE FABRY-PEROT PROFILES - AN ANALYSIS

Two techniques for recovery of the Doppler temperature from Fabry-Pero t spectrometer observations of multiple-line profiles are tested. A di rect fit of a modeled profile to the data is found to produce more con sistent results and is less sensitive to noise than the method of leas t-squares fitting to low-order Fourier-transform coefficients derived from the data. This result is unexpected since the Fourier-transform m ethod permits the reduction of noise by truncating the series of coeff icients used to determine the temperature.