Abstract
The halfwidth method used for the determination of the electron density in flares is discussed from the point of view of possible errors which may enter the obtained results. The discussion includes an analysis of errors of measurement as well as errors of the method due to: (1) our incomplete knowledge of the electron damping, (2) the assumption of constant electron temperature, (3) the presence of residual self-absorption in high Balmer lines, and (4) possibly present non-thermal motions. It is shown that the factors (2) to (4) cannot induce any relative error in n e higher than 30 % of the correct value, and the actual error usually is smaller. A comparison is made of the halfwidth-method application to active prominences and limb flares.
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Švestka, Z., Fritzová-Švestková, L. Electron density in flares I: Discussion of the halfwidth method. Sol Phys 2, 75–86 (1967). https://doi.org/10.1007/BF00155893
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DOI: https://doi.org/10.1007/BF00155893